diff options
Diffstat (limited to 'drivers/i2c/busses')
29 files changed, 1377 insertions, 37 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 0cdc8443deab..8adc0f1d7ad0 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -128,6 +128,7 @@ config I2C_I801 DNV (SOC) Broxton (SOC) Lewisburg (PCH) + Gemini Lake (SOC) This driver can also be built as a module. If so, the module will be called i2c-i801. @@ -886,6 +887,16 @@ config I2C_ST This driver can also be built as module. If so, the module will be called i2c-st. +config I2C_STM32F4 + tristate "STMicroelectronics STM32F4 I2C support" + depends on ARCH_STM32 || COMPILE_TEST + help + Enable this option to add support for STM32 I2C controller embedded + in STM32F4 SoCs. + + This driver can also be built as module. If so, the module + will be called i2c-stm32f4. + config I2C_STU300 tristate "ST Microelectronics DDC I2C interface" depends on MACH_U300 @@ -919,6 +930,17 @@ config I2C_TEGRA If you say yes to this option, support will be included for the I2C controller embedded in NVIDIA Tegra SOCs +config I2C_TEGRA_BPMP + tristate "NVIDIA Tegra BPMP I2C controller" + depends on TEGRA_BPMP + help + If you say yes to this option, support will be included for the I2C + controller embedded in NVIDIA Tegra SoCs accessed via the BPMP. + + This I2C driver is a 'virtual' I2C driver. The real driver is part + of the BPMP firmware, and this driver merely communicates with that + real driver. + config I2C_UNIPHIER tristate "UniPhier FIFO-less I2C controller" depends on ARCH_UNIPHIER || COMPILE_TEST diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 1c1bac87a9db..30b60855fbcd 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -85,9 +85,11 @@ obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o obj-$(CONFIG_I2C_SIRF) += i2c-sirf.o obj-$(CONFIG_I2C_ST) += i2c-st.o +obj-$(CONFIG_I2C_STM32F4) += i2c-stm32f4.o obj-$(CONFIG_I2C_STU300) += i2c-stu300.o obj-$(CONFIG_I2C_SUN6I_P2WI) += i2c-sun6i-p2wi.o obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o +obj-$(CONFIG_I2C_TEGRA_BPMP) += i2c-tegra-bpmp.o obj-$(CONFIG_I2C_UNIPHIER) += i2c-uniphier.o obj-$(CONFIG_I2C_UNIPHIER_F) += i2c-uniphier-f.o obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c index 0b86c6173e07..fabbb9e49161 100644 --- a/drivers/i2c/busses/i2c-at91.c +++ b/drivers/i2c/busses/i2c-at91.c @@ -820,7 +820,7 @@ static u32 at91_twi_func(struct i2c_adapter *adapter) | I2C_FUNC_SMBUS_READ_BLOCK_DATA; } -static struct i2c_algorithm at91_twi_algorithm = { +static const struct i2c_algorithm at91_twi_algorithm = { .master_xfer = at91_twi_xfer, .functionality = at91_twi_func, }; @@ -1180,6 +1180,7 @@ static int at91_twi_suspend_noirq(struct device *dev) static int at91_twi_resume_noirq(struct device *dev) { + struct at91_twi_dev *twi_dev = dev_get_drvdata(dev); int ret; if (!pm_runtime_status_suspended(dev)) { @@ -1191,6 +1192,8 @@ static int at91_twi_resume_noirq(struct device *dev) pm_runtime_mark_last_busy(dev); pm_request_autosuspend(dev); + at91_init_twi_bus(twi_dev); + return 0; } diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c index c3436f627028..cd07a69e2e93 100644 --- a/drivers/i2c/busses/i2c-bcm2835.c +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -195,7 +195,9 @@ static irqreturn_t bcm2835_i2c_isr(int this_irq, void *data) } if (val & BCM2835_I2C_S_DONE) { - if (i2c_dev->curr_msg->flags & I2C_M_RD) { + if (!i2c_dev->curr_msg) { + dev_err(i2c_dev->dev, "Got unexpected interrupt (from firmware?)\n"); + } else if (i2c_dev->curr_msg->flags & I2C_M_RD) { bcm2835_drain_rxfifo(i2c_dev); val = bcm2835_i2c_readl(i2c_dev, BCM2835_I2C_S); } diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c index 29d00c4f7824..9fe942b8c610 100644 --- a/drivers/i2c/busses/i2c-bfin-twi.c +++ b/drivers/i2c/busses/i2c-bfin-twi.c @@ -563,7 +563,7 @@ static u32 bfin_twi_functionality(struct i2c_adapter *adap) I2C_FUNC_I2C | I2C_FUNC_SMBUS_I2C_BLOCK; } -static struct i2c_algorithm bfin_twi_algorithm = { +static const struct i2c_algorithm bfin_twi_algorithm = { .master_xfer = bfin_twi_master_xfer, .smbus_xfer = bfin_twi_smbus_xfer, .functionality = bfin_twi_functionality, diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c index 9b36a7b3befd..eb76b76f4754 100644 --- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c +++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c @@ -154,8 +154,10 @@ static int ec_i2c_parse_response(const u8 *buf, struct i2c_msg i2c_msgs[], resp = (const struct ec_response_i2c_passthru *)buf; if (resp->i2c_status & EC_I2C_STATUS_TIMEOUT) return -ETIMEDOUT; + else if (resp->i2c_status & EC_I2C_STATUS_NAK) + return -ENXIO; else if (resp->i2c_status & EC_I2C_STATUS_ERROR) - return -EREMOTEIO; + return -EIO; /* Other side could send us back fewer messages, but not more */ if (resp->num_msgs > *num) @@ -222,10 +224,8 @@ static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[], } result = ec_i2c_parse_response(msg->data, i2c_msgs, &num); - if (result < 0) { - dev_err(dev, "Error parsing EC i2c message %d\n", result); + if (result < 0) goto exit; - } /* Indicate success by saying how many messages were sent */ result = num; diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c index e9db857c6226..7a3faa551cf8 100644 --- a/drivers/i2c/busses/i2c-designware-core.c +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -820,7 +820,7 @@ static u32 i2c_dw_func(struct i2c_adapter *adap) return dev->functionality; } -static struct i2c_algorithm i2c_dw_algo = { +static const struct i2c_algorithm i2c_dw_algo = { .master_xfer = i2c_dw_xfer, .functionality = i2c_dw_func, }; diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c index 5ce71ce7b6c4..bdeab0174fec 100644 --- a/drivers/i2c/busses/i2c-eg20t.c +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -715,7 +715,7 @@ static u32 pch_i2c_func(struct i2c_adapter *adap) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; } -static struct i2c_algorithm pch_algorithm = { +static const struct i2c_algorithm pch_algorithm = { .master_xfer = pch_i2c_xfer, .functionality = pch_i2c_func }; diff --git a/drivers/i2c/busses/i2c-emev2.c b/drivers/i2c/busses/i2c-emev2.c index 96bb4e749012..312912708854 100644 --- a/drivers/i2c/busses/i2c-emev2.c +++ b/drivers/i2c/busses/i2c-emev2.c @@ -347,7 +347,7 @@ static int em_i2c_unreg_slave(struct i2c_client *slave) return 0; } -static struct i2c_algorithm em_i2c_algo = { +static const struct i2c_algorithm em_i2c_algo = { .master_xfer = em_i2c_xfer, .functionality = em_i2c_func, .reg_slave = em_i2c_reg_slave, diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c index bea607149972..cbd93ce0661f 100644 --- a/drivers/i2c/busses/i2c-exynos5.c +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -130,12 +130,32 @@ /* I2C_TRANS_STATUS register bits */ #define HSI2C_MASTER_BUSY (1u << 17) #define HSI2C_SLAVE_BUSY (1u << 16) + +/* I2C_TRANS_STATUS register bits for Exynos5 variant */ #define HSI2C_TIMEOUT_AUTO (1u << 4) #define HSI2C_NO_DEV (1u << 3) #define HSI2C_NO_DEV_ACK (1u << 2) #define HSI2C_TRANS_ABORT (1u << 1) #define HSI2C_TRANS_DONE (1u << 0) +/* I2C_TRANS_STATUS register bits for Exynos7 variant */ +#define HSI2C_MASTER_ST_MASK 0xf +#define HSI2C_MASTER_ST_IDLE 0x0 +#define HSI2C_MASTER_ST_START 0x1 +#define HSI2C_MASTER_ST_RESTART 0x2 +#define HSI2C_MASTER_ST_STOP 0x3 +#define HSI2C_MASTER_ST_MASTER_ID 0x4 +#define HSI2C_MASTER_ST_ADDR0 0x5 +#define HSI2C_MASTER_ST_ADDR1 0x6 +#define HSI2C_MASTER_ST_ADDR2 0x7 +#define HSI2C_MASTER_ST_ADDR_SR 0x8 +#define HSI2C_MASTER_ST_READ 0x9 +#define HSI2C_MASTER_ST_WRITE 0xa +#define HSI2C_MASTER_ST_NO_ACK 0xb +#define HSI2C_MASTER_ST_LOSE 0xc +#define HSI2C_MASTER_ST_WAIT 0xd +#define HSI2C_MASTER_ST_WAIT_CMD 0xe + /* I2C_ADDR register bits */ #define HSI2C_SLV_ADDR_SLV(x) ((x & 0x3ff) << 0) #define HSI2C_SLV_ADDR_MAS(x) ((x & 0x3ff) << 10) @@ -437,6 +457,7 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) int_status = readl(i2c->regs + HSI2C_INT_STATUS); writel(int_status, i2c->regs + HSI2C_INT_STATUS); + trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); /* handle interrupt related to the transfer status */ if (i2c->variant->hw == HSI2C_EXYNOS7) { @@ -460,8 +481,12 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) i2c->state = -ETIMEDOUT; goto stop; } + + if ((trans_status & HSI2C_MASTER_ST_MASK) == HSI2C_MASTER_ST_LOSE) { + i2c->state = -EAGAIN; + goto stop; + } } else if (int_status & HSI2C_INT_I2C) { - trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); if (trans_status & HSI2C_NO_DEV_ACK) { dev_dbg(i2c->dev, "No ACK from device\n"); i2c->state = -ENXIO; @@ -502,8 +527,13 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) fifo_level = HSI2C_TX_FIFO_LVL(fifo_status); len = i2c->variant->fifo_depth - fifo_level; - if (len > (i2c->msg->len - i2c->msg_ptr)) + if (len > (i2c->msg->len - i2c->msg_ptr)) { + u32 int_en = readl(i2c->regs + HSI2C_INT_ENABLE); + + int_en &= ~HSI2C_INT_TX_ALMOSTEMPTY_EN; + writel(int_en, i2c->regs + HSI2C_INT_ENABLE); len = i2c->msg->len - i2c->msg_ptr; + } while (len > 0) { byte = i2c->msg->buf[i2c->msg_ptr++]; diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index e242db43774b..6484fa6dbb84 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -65,6 +65,7 @@ * Lewisburg (PCH) 0xa1a3 32 hard yes yes yes * Lewisburg Supersku (PCH) 0xa223 32 hard yes yes yes * Kaby Lake PCH-H (PCH) 0xa2a3 32 hard yes yes yes + * Gemini Lake (SOC) 0x31d4 32 hard yes yes yes * * Features supported by this driver: * Software PEC no @@ -213,6 +214,7 @@ #define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS 0x2292 #define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS 0x2330 #define PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS 0x23b0 +#define PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS 0x31d4 #define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS 0x3b30 #define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS 0x5ad4 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS 0x8c22 @@ -1012,6 +1014,7 @@ static const struct pci_device_id i801_ids[] = { { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS) }, + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) }, diff --git a/drivers/i2c/busses/i2c-ibm_iic.c b/drivers/i2c/busses/i2c-ibm_iic.c index 412b91d255ad..961c5f42d956 100644 --- a/drivers/i2c/busses/i2c-ibm_iic.c +++ b/drivers/i2c/busses/i2c-ibm_iic.c @@ -37,6 +37,8 @@ #include <linux/delay.h> #include <linux/slab.h> #include <linux/interrupt.h> +#include <linux/sched/signal.h> + #include <asm/irq.h> #include <linux/io.h> #include <linux/i2c.h> diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c index 3310f2e0dbd3..e86801a63120 100644 --- a/drivers/i2c/busses/i2c-imx-lpi2c.c +++ b/drivers/i2c/busses/i2c-imx-lpi2c.c @@ -538,7 +538,7 @@ static u32 lpi2c_imx_func(struct i2c_adapter *adapter) I2C_FUNC_SMBUS_READ_BLOCK_DATA; } -static struct i2c_algorithm lpi2c_imx_algo = { +static const struct i2c_algorithm lpi2c_imx_algo = { .master_xfer = lpi2c_imx_xfer, .functionality = lpi2c_imx_func, }; diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 47fc1f1acff7..95ed17183e73 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -1037,7 +1037,7 @@ static u32 i2c_imx_func(struct i2c_adapter *adapter) | I2C_FUNC_SMBUS_READ_BLOCK_DATA; } -static struct i2c_algorithm i2c_imx_algo = { +static const struct i2c_algorithm i2c_imx_algo = { .master_xfer = i2c_imx_xfer, .functionality = i2c_imx_func, }; diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index 565a49a0c564..96caf378b1dc 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -15,7 +15,7 @@ #include <linux/kernel.h> #include <linux/module.h> -#include <linux/sched.h> +#include <linux/sched/signal.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/of_platform.h> diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index b4dec0841bc2..a50bd6891e27 100644 --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -977,11 +977,32 @@ mv64xxx_i2c_remove(struct platform_device *dev) return 0; } +#ifdef CONFIG_PM +static int mv64xxx_i2c_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(pdev); + + mv64xxx_i2c_hw_init(drv_data); + + return 0; +} + +static const struct dev_pm_ops mv64xxx_i2c_pm = { + .resume = mv64xxx_i2c_resume, +}; + +#define mv64xxx_i2c_pm_ops (&mv64xxx_i2c_pm) +#else +#define mv64xxx_i2c_pm_ops NULL +#endif + static struct platform_driver mv64xxx_i2c_driver = { .probe = mv64xxx_i2c_probe, .remove = mv64xxx_i2c_remove, .driver = { .name = MV64XXX_I2C_CTLR_NAME, + .pm = mv64xxx_i2c_pm_ops, .of_match_table = mv64xxx_i2c_of_match_table, }, }; diff --git a/drivers/i2c/busses/i2c-nforce2.c b/drivers/i2c/busses/i2c-nforce2.c index 374b35e7e450..3241bb9d6c18 100644 --- a/drivers/i2c/busses/i2c-nforce2.c +++ b/drivers/i2c/busses/i2c-nforce2.c @@ -296,7 +296,7 @@ static u32 nforce2_func(struct i2c_adapter *adapter) I2C_FUNC_SMBUS_BLOCK_DATA : 0); } -static struct i2c_algorithm smbus_algorithm = { +static const struct i2c_algorithm smbus_algorithm = { .smbus_xfer = nforce2_access, .functionality = nforce2_func, }; diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h index e160f838c254..aa3c8f4771c1 100644 --- a/drivers/i2c/busses/i2c-octeon-core.h +++ b/drivers/i2c/busses/i2c-octeon-core.h @@ -6,7 +6,6 @@ #include <linux/i2c-smbus.h> #include <linux/io.h> #include <linux/kernel.h> -#include <linux/pci.h> /* Controller command patterns */ #define SW_TWSI_V BIT_ULL(63) /* Valid bit */ @@ -118,9 +117,6 @@ struct octeon_i2c { void (*hlc_int_disable)(struct octeon_i2c *); atomic_t int_enable_cnt; atomic_t hlc_int_enable_cnt; -#if IS_ENABLED(CONFIG_I2C_THUNDERX) - struct msix_entry i2c_msix; -#endif struct i2c_smbus_alert_setup alert_data; struct i2c_client *ara; }; diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index c7da0c42baee..1ebb5e947e0b 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -1504,7 +1504,7 @@ static int omap_i2c_runtime_resume(struct device *dev) return 0; } -static struct dev_pm_ops omap_i2c_pm_ops = { +static const struct dev_pm_ops omap_i2c_pm_ops = { SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend, omap_i2c_runtime_resume, NULL) }; diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c index 6263ea82d6ac..8f11d347b3ec 100644 --- a/drivers/i2c/busses/i2c-riic.c +++ b/drivers/i2c/busses/i2c-riic.c @@ -80,6 +80,7 @@ #define ICIER_TEIE 0x40 #define ICIER_RIE 0x20 #define ICIER_NAKIE 0x10 +#define ICIER_SPIE 0x08 #define ICSR2_NACKF 0x10 @@ -216,11 +217,10 @@ static irqreturn_t riic_tend_isr(int irq, void *data) return IRQ_NONE; } - if (riic->is_last || riic->err) + if (riic->is_last || riic->err) { + riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER); writeb(ICCR2_SP, riic->base + RIIC_ICCR2); - - writeb(0, riic->base + RIIC_ICIER); - complete(&riic->msg_done); + } return IRQ_HANDLED; } @@ -240,13 +240,13 @@ static irqreturn_t riic_rdrf_isr(int irq, void *data) if (riic->bytes_left == 1) { /* STOP must come before we set ACKBT! */ - if (riic->is_last) + if (riic->is_last) { + riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER); writeb(ICCR2_SP, riic->base + RIIC_ICCR2); + } riic_clear_set_bit(riic, 0, ICMR3_ACKBT, RIIC_ICMR3); - writeb(0, riic->base + RIIC_ICIER); - complete(&riic->msg_done); } else { riic_clear_set_bit(riic, ICMR3_ACKBT, 0, RIIC_ICMR3); } @@ -259,6 +259,21 @@ static irqreturn_t riic_rdrf_isr(int irq, void *data) return IRQ_HANDLED; } +static irqreturn_t riic_stop_isr(int irq, void *data) +{ + struct riic_dev *riic = data; + + /* read back registers to confirm writes have fully propagated */ + writeb(0, riic->base + RIIC_ICSR2); + readb(riic->base + RIIC_ICSR2); + writeb(0, riic->base + RIIC_ICIER); + readb(riic->base + RIIC_ICIER); + + complete(&riic->msg_done); + + return IRQ_HANDLED; +} + static u32 riic_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; @@ -326,6 +341,7 @@ static struct riic_irq_desc riic_irqs[] = { { .res_num = 0, .isr = riic_tend_isr, .name = "riic-tend" }, { .res_num = 1, .isr = riic_rdrf_isr, .name = "riic-rdrf" }, { .res_num = 2, .isr = riic_tdre_isr, .name = "riic-tdre" }, + { .res_num = 3, .isr = riic_stop_isr, .name = "riic-stop" }, { .res_num = 5, .isr = riic_tend_isr, .name = "riic-nack" }, }; diff --git a/drivers/i2c/busses/i2c-robotfuzz-osif.c b/drivers/i2c/busses/i2c-robotfuzz-osif.c index 89d8b41b6668..9c0f52b7ff7e 100644 --- a/drivers/i2c/busses/i2c-robotfuzz-osif.c +++ b/drivers/i2c/busses/i2c-robotfuzz-osif.c @@ -117,7 +117,7 @@ static u32 osif_func(struct i2c_adapter *adapter) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; } -static struct i2c_algorithm osif_algorithm = { +static const struct i2c_algorithm osif_algorithm = { .master_xfer = osif_xfer, .functionality = osif_func, }; diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index 3d9ebe6e5716..3d7559348745 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -781,7 +781,7 @@ static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; } -static struct i2c_algorithm sh_mobile_i2c_algorithm = { +static const struct i2c_algorithm sh_mobile_i2c_algorithm = { .functionality = sh_mobile_i2c_func, .master_xfer = sh_mobile_i2c_xfer, }; diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c index 1371547ce1a3..1eb9fa82dcfd 100644 --- a/drivers/i2c/busses/i2c-st.c +++ b/drivers/i2c/busses/i2c-st.c @@ -776,7 +776,7 @@ static u32 st_i2c_func(struct i2c_adapter *adap) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; } -static struct i2c_algorithm st_i2c_algo = { +static const struct i2c_algorithm st_i2c_algo = { .master_xfer = st_i2c_xfer, .functionality = st_i2c_func, }; diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c new file mode 100644 index 000000000000..f9dd7e86b861 --- /dev/null +++ b/drivers/i2c/busses/i2c-stm32f4.c @@ -0,0 +1,897 @@ +/* + * Driver for STMicroelectronics STM32 I2C controller + * + * This I2C controller is described in the STM32F429/439 Soc reference manual. + * Please see below a link to the documentation: + * http://www.st.com/resource/en/reference_manual/DM00031020.pdf + * + * Copyright (C) M'boumba Cedric Madianga 2016 + * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> + * + * This driver is based on i2c-st.c + * + * License terms: GNU General Public License (GPL), version 2 + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset.h> + +/* STM32F4 I2C offset registers */ +#define STM32F4_I2C_CR1 0x00 +#define STM32F4_I2C_CR2 0x04 +#define STM32F4_I2C_DR 0x10 +#define STM32F4_I2C_SR1 0x14 +#define STM32F4_I2C_SR2 0x18 +#define STM32F4_I2C_CCR 0x1C +#define STM32F4_I2C_TRISE 0x20 +#define STM32F4_I2C_FLTR 0x24 + +/* STM32F4 I2C control 1*/ +#define STM32F4_I2C_CR1_POS BIT(11) +#define STM32F4_I2C_CR1_ACK BIT(10) +#define STM32F4_I2C_CR1_STOP BIT(9) +#define STM32F4_I2C_CR1_START BIT(8) +#define STM32F4_I2C_CR1_PE BIT(0) + +/* STM32F4 I2C control 2 */ +#define STM32F4_I2C_CR2_FREQ_MASK GENMASK(5, 0) +#define STM32F4_I2C_CR2_FREQ(n) ((n) & STM32F4_I2C_CR2_FREQ_MASK) +#define STM32F4_I2C_CR2_ITBUFEN BIT(10) +#define STM32F4_I2C_CR2_ITEVTEN BIT(9) +#define STM32F4_I2C_CR2_ITERREN BIT(8) +#define STM32F4_I2C_CR2_IRQ_MASK (STM32F4_I2C_CR2_ITBUFEN | \ + STM32F4_I2C_CR2_ITEVTEN | \ + STM32F4_I2C_CR2_ITERREN) + +/* STM32F4 I2C Status 1 */ +#define STM32F4_I2C_SR1_AF BIT(10) +#define STM32F4_I2C_SR1_ARLO BIT(9) +#define STM32F4_I2C_SR1_BERR BIT(8) +#define STM32F4_I2C_SR1_TXE BIT(7) +#define STM32F4_I2C_SR1_RXNE BIT(6) +#define STM32F4_I2C_SR1_BTF BIT(2) +#define STM32F4_I2C_SR1_ADDR BIT(1) +#define STM32F4_I2C_SR1_SB BIT(0) +#define STM32F4_I2C_SR1_ITEVTEN_MASK (STM32F4_I2C_SR1_BTF | \ + STM32F4_I2C_SR1_ADDR | \ + STM32F4_I2C_SR1_SB) +#define STM32F4_I2C_SR1_ITBUFEN_MASK (STM32F4_I2C_SR1_TXE | \ + STM32F4_I2C_SR1_RXNE) +#define STM32F4_I2C_SR1_ITERREN_MASK (STM32F4_I2C_SR1_AF | \ + STM32F4_I2C_SR1_ARLO | \ + STM32F4_I2C_SR1_BERR) + +/* STM32F4 I2C Status 2 */ +#define STM32F4_I2C_SR2_BUSY BIT(1) + +/* STM32F4 I2C Control Clock */ +#define STM32F4_I2C_CCR_CCR_MASK GENMASK(11, 0) +#define STM32F4_I2C_CCR_CCR(n) ((n) & STM32F4_I2C_CCR_CCR_MASK) +#define STM32F4_I2C_CCR_FS BIT(15) +#define STM32F4_I2C_CCR_DUTY BIT(14) + +/* STM32F4 I2C Trise */ +#define STM32F4_I2C_TRISE_VALUE_MASK GENMASK(5, 0) +#define STM32F4_I2C_TRISE_VALUE(n) ((n) & STM32F4_I2C_TRISE_VALUE_MASK) + +#define STM32F4_I2C_MIN_STANDARD_FREQ 2U +#define STM32F4_I2C_MIN_FAST_FREQ 6U +#define STM32F4_I2C_MAX_FREQ 46U +#define HZ_TO_MHZ 1000000 + +enum stm32f4_i2c_speed { + STM32F4_I2C_SPEED_STANDARD, /* 100 kHz */ + STM32F4_I2C_SPEED_FAST, /* 400 kHz */ + STM32F4_I2C_SPEED_END, +}; + +/** + * struct stm32f4_i2c_msg - client specific data + * @addr: 8-bit slave addr, including r/w bit + * @count: number of bytes to be transferred + * @buf: data buffer + * @result: result of the transfer + * @stop: last I2C msg to be sent, i.e. STOP to be generated + */ +struct stm32f4_i2c_msg { + u8 addr; + u32 count; + u8 *buf; + int result; + bool stop; +}; + +/** + * struct stm32f4_i2c_dev - private data of the controller + * @adap: I2C adapter for this controller + * @dev: device for this controller + * @base: virtual memory area + * @complete: completion of I2C message + * @clk: hw i2c clock + * @speed: I2C clock frequency of the controller. Standard or Fast are supported + * @parent_rate: I2C clock parent rate in MHz + * @msg: I2C transfer information + */ +struct stm32f4_i2c_dev { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + struct completion complete; + struct clk *clk; + int speed; + int parent_rate; + struct stm32f4_i2c_msg msg; +}; + +static inline void stm32f4_i2c_set_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) | mask, reg); +} + +static inline void stm32f4_i2c_clr_bits(void __iomem *reg, u32 mask) +{ + writel_relaxed(readl_relaxed(reg) & ~mask, reg); +} + +static void stm32f4_i2c_disable_irq(struct stm32f4_i2c_dev *i2c_dev) +{ + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_IRQ_MASK); +} + +static int stm32f4_i2c_set_periph_clk_freq(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 freq; + u32 cr2 = 0; + + i2c_dev->parent_rate = clk_get_rate(i2c_dev->clk); + freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ); + + if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) { + /* + * To reach 100 kHz, the parent clk frequency should be between + * a minimum value of 2 MHz and a maximum value of 46 MHz due + * to hardware limitation + */ + if (freq < STM32F4_I2C_MIN_STANDARD_FREQ || + freq > STM32F4_I2C_MAX_FREQ) { + dev_err(i2c_dev->dev, + "bad parent clk freq for standard mode\n"); + return -EINVAL; + } + } else { + /* + * To be as close as possible to 400 kHz, the parent clk + * frequency should be between a minimum value of 6 MHz and a + * maximum value of 46 MHz due to hardware limitation + */ + if (freq < STM32F4_I2C_MIN_FAST_FREQ || + freq > STM32F4_I2C_MAX_FREQ) { + dev_err(i2c_dev->dev, + "bad parent clk freq for fast mode\n"); + return -EINVAL; + } + } + + cr2 |= STM32F4_I2C_CR2_FREQ(freq); + writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2); + + return 0; +} + +static void stm32f4_i2c_set_rise_time(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ); + u32 trise; + + /* + * These bits must be programmed with the maximum SCL rise time given in + * the I2C bus specification, incremented by 1. + * + * In standard mode, the maximum allowed SCL rise time is 1000 ns. + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be + * programmed with 0x9. (1000 ns / 125 ns + 1) + * So, for I2C standard mode TRISE = FREQ[5:0] + 1 + * + * In fast mode, the maximum allowed SCL rise time is 300 ns. + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be + * programmed with 0x3. (300 ns / 125 ns + 1) + * So, for I2C fast mode TRISE = FREQ[5:0] * 300 / 1000 + 1 + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that parent rate + * is not higher than 46 MHz . As a result trise is at most 4 bits wide + * and so fits into the TRISE bits [5:0]. + */ + if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) + trise = freq + 1; + else + trise = freq * 3 / 10 + 1; + + writel_relaxed(STM32F4_I2C_TRISE_VALUE(trise), + i2c_dev->base + STM32F4_I2C_TRISE); +} + +static void stm32f4_i2c_set_speed_mode(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 val; + u32 ccr = 0; + + if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) { + /* + * In standard mode: + * t_scl_high = t_scl_low = CCR * I2C parent clk period + * So to reach 100 kHz, we have: + * CCR = I2C parent rate / 100 kHz >> 1 + * + * For example with parent rate = 2 MHz: + * CCR = 2000000 / (100000 << 1) = 10 + * t_scl_high = t_scl_low = 10 * (1 / 2000000) = 5000 ns + * t_scl_high + t_scl_low = 10000 ns so 100 kHz is reached + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that + * parent rate is not higher than 46 MHz . As a result val + * is at most 8 bits wide and so fits into the CCR bits [11:0]. + */ + val = i2c_dev->parent_rate / (100000 << 1); + } else { + /* + * In fast mode, we compute CCR with duty = 0 as with low + * frequencies we are not able to reach 400 kHz. + * In that case: + * t_scl_high = CCR * I2C parent clk period + * t_scl_low = 2 * CCR * I2C parent clk period + * So, CCR = I2C parent rate / (400 kHz * 3) + * + * For example with parent rate = 6 MHz: + * CCR = 6000000 / (400000 * 3) = 5 + * t_scl_high = 5 * (1 / 6000000) = 833 ns > 600 ns + * t_scl_low = 2 * 5 * (1 / 6000000) = 1667 ns > 1300 ns + * t_scl_high + t_scl_low = 2500 ns so 400 kHz is reached + * + * Function stm32f4_i2c_set_periph_clk_freq made sure that + * parent rate is not higher than 46 MHz . As a result val + * is at most 6 bits wide and so fits into the CCR bits [11:0]. + */ + val = DIV_ROUND_UP(i2c_dev->parent_rate, 400000 * 3); + + /* Select Fast mode */ + ccr |= STM32F4_I2C_CCR_FS; + } + + ccr |= STM32F4_I2C_CCR_CCR(val); + writel_relaxed(ccr, i2c_dev->base + STM32F4_I2C_CCR); +} + +/** + * stm32f4_i2c_hw_config() - Prepare I2C block + * @i2c_dev: Controller's private data + */ +static int stm32f4_i2c_hw_config(struct stm32f4_i2c_dev *i2c_dev) +{ + int ret; + + ret = stm32f4_i2c_set_periph_clk_freq(i2c_dev); + if (ret) + return ret; + + stm32f4_i2c_set_rise_time(i2c_dev); + + stm32f4_i2c_set_speed_mode(i2c_dev); + + /* Enable I2C */ + writel_relaxed(STM32F4_I2C_CR1_PE, i2c_dev->base + STM32F4_I2C_CR1); + + return 0; +} + +static int stm32f4_i2c_wait_free_bus(struct stm32f4_i2c_dev *i2c_dev) +{ + u32 status; + int ret; + + ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F4_I2C_SR2, + status, + !(status & STM32F4_I2C_SR2_BUSY), + 10, 1000); + if (ret) { + dev_dbg(i2c_dev->dev, "bus not free\n"); + ret = -EBUSY; + } + + return ret; +} + +/** + * stm32f4_i2c_write_ byte() - Write a byte in the data register + * @i2c_dev: Controller's private data + * @byte: Data to write in the register + */ +static void stm32f4_i2c_write_byte(struct stm32f4_i2c_dev *i2c_dev, u8 byte) +{ + writel_relaxed(byte, i2c_dev->base + STM32F4_I2C_DR); +} + +/** + * stm32f4_i2c_write_msg() - Fill the data register in write mode + * @i2c_dev: Controller's private data + * + * This function fills the data register with I2C transfer buffer + */ +static void stm32f4_i2c_write_msg(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + + stm32f4_i2c_write_byte(i2c_dev, *msg->buf++); + msg->count--; +} + +static void stm32f4_i2c_read_msg(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 rbuf; + + rbuf = readl_relaxed(i2c_dev->base + STM32F4_I2C_DR); + *msg->buf++ = rbuf; + msg->count--; +} + +static void stm32f4_i2c_terminate_xfer(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + stm32f4_i2c_disable_irq(i2c_dev); + + reg = i2c_dev->base + STM32F4_I2C_CR1; + if (msg->stop) + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + else + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + + complete(&i2c_dev->complete); +} + +/** + * stm32f4_i2c_handle_write() - Handle FIFO empty interrupt in case of write + * @i2c_dev: Controller's private data + */ +static void stm32f4_i2c_handle_write(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + if (msg->count) { + stm32f4_i2c_write_msg(i2c_dev); + if (!msg->count) { + /* + * Disable buffer interrupts for RX not empty and TX + * empty events + */ + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN); + } + } else { + stm32f4_i2c_terminate_xfer(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_read() - Handle FIFO empty interrupt in case of read + * @i2c_dev: Controller's private data + * + * This function is called when a new data is received in data register + */ +static void stm32f4_i2c_handle_read(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR2; + + switch (msg->count) { + case 1: + stm32f4_i2c_disable_irq(i2c_dev); + stm32f4_i2c_read_msg(i2c_dev); + complete(&i2c_dev->complete); + break; + /* + * For 2-byte reception, 3-byte reception and for Data N-2, N-1 and N + * for N-byte reception with N > 3, we do not have to read the data + * register when RX not empty event occurs as we have to wait for byte + * transferred finished event before reading data. + * So, here we just disable buffer interrupt in order to avoid another + * system preemption due to RX not empty event. + */ + case 2: + case 3: + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR2_ITBUFEN); + break; + /* + * For N byte reception with N > 3 we directly read data register + * until N-2 data. + */ + default: + stm32f4_i2c_read_msg(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_rx_done() - Handle byte transfer finished interrupt + * in case of read + * @i2c_dev: Controller's private data + * + * This function is called when a new data is received in the shift register + * but data register has not been read yet. + */ +static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg; + u32 mask; + int i; + + switch (msg->count) { + case 2: + /* + * In order to correctly send the Stop or Repeated Start + * condition on the I2C bus, the STOP/START bit has to be set + * before reading the last two bytes (data N-1 and N). + * After that, we could read the last two bytes, disable + * remaining interrupts and notify the end of xfer to the + * client + */ + reg = i2c_dev->base + STM32F4_I2C_CR1; + if (msg->stop) + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + else + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + + for (i = 2; i > 0; i--) + stm32f4_i2c_read_msg(i2c_dev); + + reg = i2c_dev->base + STM32F4_I2C_CR2; + mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN; + stm32f4_i2c_clr_bits(reg, mask); + + complete(&i2c_dev->complete); + break; + case 3: + /* + * In order to correctly generate the NACK pulse after the last + * received data byte, we have to enable NACK before reading N-2 + * data + */ + reg = i2c_dev->base + STM32F4_I2C_CR1; + stm32f4_i2c_clr_bits(reg, STM32F4_I2C_CR1_ACK); + stm32f4_i2c_read_msg(i2c_dev); + break; + default: + stm32f4_i2c_read_msg(i2c_dev); + } +} + +/** + * stm32f4_i2c_handle_rx_addr() - Handle address matched interrupt in case of + * master receiver + * @i2c_dev: Controller's private data + */ +static void stm32f4_i2c_handle_rx_addr(struct stm32f4_i2c_dev *i2c_dev) +{ + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 cr1; + + switch (msg->count) { + case 0: + stm32f4_i2c_terminate_xfer(i2c_dev); + + /* Clear ADDR flag */ + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + case 1: + /* + * Single byte reception: + * Enable NACK and reset POS (Acknowledge position). + * Then, clear ADDR flag and set STOP or RepSTART. + * In that way, the NACK and STOP or RepStart pulses will be + * sent as soon as the byte will be received in shift register + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 &= ~(STM32F4_I2C_CR1_ACK | STM32F4_I2C_CR1_POS); + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + + if (msg->stop) + cr1 |= STM32F4_I2C_CR1_STOP; + else + cr1 |= STM32F4_I2C_CR1_START; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + break; + case 2: + /* + * 2-byte reception: + * Enable NACK, set POS (NACK position) and clear ADDR flag. + * In that way, NACK will be sent for the next byte which will + * be received in the shift register instead of the current + * one. + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 &= ~STM32F4_I2C_CR1_ACK; + cr1 |= STM32F4_I2C_CR1_POS; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + + default: + /* + * N-byte reception: + * Enable ACK, reset POS (ACK postion) and clear ADDR flag. + * In that way, ACK will be sent as soon as the current byte + * will be received in the shift register + */ + cr1 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR1); + cr1 |= STM32F4_I2C_CR1_ACK; + cr1 &= ~STM32F4_I2C_CR1_POS; + writel_relaxed(cr1, i2c_dev->base + STM32F4_I2C_CR1); + + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + break; + } +} + +/** + * stm32f4_i2c_isr_event() - Interrupt routine for I2C bus event + * @irq: interrupt number + * @data: Controller's private data + */ +static irqreturn_t stm32f4_i2c_isr_event(int irq, void *data) +{ + struct stm32f4_i2c_dev *i2c_dev = data; + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + u32 possible_status = STM32F4_I2C_SR1_ITEVTEN_MASK; + u32 status, ien, event, cr2; + + cr2 = readl_relaxed(i2c_dev->base + STM32F4_I2C_CR2); + ien = cr2 & STM32F4_I2C_CR2_IRQ_MASK; + + /* Update possible_status if buffer interrupt is enabled */ + if (ien & STM32F4_I2C_CR2_ITBUFEN) + possible_status |= STM32F4_I2C_SR1_ITBUFEN_MASK; + + status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1); + event = status & possible_status; + if (!event) { + dev_dbg(i2c_dev->dev, + "spurious evt irq (status=0x%08x, ien=0x%08x)\n", + status, ien); + return IRQ_NONE; + } + + /* Start condition generated */ + if (event & STM32F4_I2C_SR1_SB) + stm32f4_i2c_write_byte(i2c_dev, msg->addr); + + /* I2C Address sent */ + if (event & STM32F4_I2C_SR1_ADDR) { + if (msg->addr & I2C_M_RD) + stm32f4_i2c_handle_rx_addr(i2c_dev); + else + readl_relaxed(i2c_dev->base + STM32F4_I2C_SR2); + + /* + * Enable buffer interrupts for RX not empty and TX empty + * events + */ + cr2 |= STM32F4_I2C_CR2_ITBUFEN; + writel_relaxed(cr2, i2c_dev->base + STM32F4_I2C_CR2); + } + + /* TX empty */ + if ((event & STM32F4_I2C_SR1_TXE) && !(msg->addr & I2C_M_RD)) + stm32f4_i2c_handle_write(i2c_dev); + + /* RX not empty */ + if ((event & STM32F4_I2C_SR1_RXNE) && (msg->addr & I2C_M_RD)) + stm32f4_i2c_handle_read(i2c_dev); + + /* + * The BTF (Byte Transfer finished) event occurs when: + * - in reception : a new byte is received in the shift register + * but the previous byte has not been read yet from data register + * - in transmission: a new byte should be sent but the data register + * has not been written yet + */ + if (event & STM32F4_I2C_SR1_BTF) { + if (msg->addr & I2C_M_RD) + stm32f4_i2c_handle_rx_done(i2c_dev); + else + stm32f4_i2c_handle_write(i2c_dev); + } + + return IRQ_HANDLED; +} + +/** + * stm32f4_i2c_isr_error() - Interrupt routine for I2C bus error + * @irq: interrupt number + * @data: Controller's private data + */ +static irqreturn_t stm32f4_i2c_isr_error(int irq, void *data) +{ + struct stm32f4_i2c_dev *i2c_dev = data; + struct stm32f4_i2c_msg *msg = &i2c_dev->msg; + void __iomem *reg; + u32 status; + + status = readl_relaxed(i2c_dev->base + STM32F4_I2C_SR1); + + /* Arbitration lost */ + if (status & STM32F4_I2C_SR1_ARLO) { + status &= ~STM32F4_I2C_SR1_ARLO; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EAGAIN; + } + + /* + * Acknowledge failure: + * In master transmitter mode a Stop must be generated by software + */ + if (status & STM32F4_I2C_SR1_AF) { + if (!(msg->addr & I2C_M_RD)) { + reg = i2c_dev->base + STM32F4_I2C_CR1; + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_STOP); + } + status &= ~STM32F4_I2C_SR1_AF; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EIO; + } + + /* Bus error */ + if (status & STM32F4_I2C_SR1_BERR) { + status &= ~STM32F4_I2C_SR1_BERR; + writel_relaxed(status, i2c_dev->base + STM32F4_I2C_SR1); + msg->result = -EIO; + } + + stm32f4_i2c_disable_irq(i2c_dev); + complete(&i2c_dev->complete); + + return IRQ_HANDLED; +} + +/** + * stm32f4_i2c_xfer_msg() - Transfer a single I2C message + * @i2c_dev: Controller's private data + * @msg: I2C message to transfer + * @is_first: first message of the sequence + * @is_last: last message of the sequence + */ +static int stm32f4_i2c_xfer_msg(struct stm32f4_i2c_dev *i2c_dev, + struct i2c_msg *msg, bool is_first, + bool is_last) +{ + struct stm32f4_i2c_msg *f4_msg = &i2c_dev->msg; + void __iomem *reg = i2c_dev->base + STM32F4_I2C_CR1; + unsigned long timeout; + u32 mask; + int ret; + + f4_msg->addr = i2c_8bit_addr_from_msg(msg); + f4_msg->buf = msg->buf; + f4_msg->count = msg->len; + f4_msg->result = 0; + f4_msg->stop = is_last; + + reinit_completion(&i2c_dev->complete); + + /* Enable events and errors interrupts */ + mask = STM32F4_I2C_CR2_ITEVTEN | STM32F4_I2C_CR2_ITERREN; + stm32f4_i2c_set_bits(i2c_dev->base + STM32F4_I2C_CR2, mask); + + if (is_first) { + ret = stm32f4_i2c_wait_free_bus(i2c_dev); + if (ret) + return ret; + + /* START generation */ + stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START); + } + + timeout = wait_for_completion_timeout(&i2c_dev->complete, + i2c_dev->adap.timeout); + ret = f4_msg->result; + + if (!timeout) + ret = -ETIMEDOUT; + + return ret; +} + +/** + * stm32f4_i2c_xfer() - Transfer combined I2C message + * @i2c_adap: Adapter pointer to the controller + * @msgs: Pointer to data to be written. + * @num: Number of messages to be executed + */ +static int stm32f4_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], + int num) +{ + struct stm32f4_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); + int ret, i; + + ret = clk_enable(i2c_dev->clk); + if (ret) { + dev_err(i2c_dev->dev, "Failed to enable clock\n"); + return ret; + } + + for (i = 0; i < num && !ret; i++) + ret = stm32f4_i2c_xfer_msg(i2c_dev, &msgs[i], i == 0, + i == num - 1); + + clk_disable(i2c_dev->clk); + + return (ret < 0) ? ret : num; +} + +static u32 stm32f4_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static struct i2c_algorithm stm32f4_i2c_algo = { + .master_xfer = stm32f4_i2c_xfer, + .functionality = stm32f4_i2c_func, +}; + +static int stm32f4_i2c_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct stm32f4_i2c_dev *i2c_dev; + struct resource *res; + u32 irq_event, irq_error, clk_rate; + struct i2c_adapter *adap; + struct reset_control *rst; + int ret; + + i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); + if (!i2c_dev) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + i2c_dev->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(i2c_dev->base)) + return PTR_ERR(i2c_dev->base); + + irq_event = irq_of_parse_and_map(np, 0); + if (!irq_event) { + dev_err(&pdev->dev, "IRQ event missing or invalid\n"); + return -EINVAL; + } + + irq_error = irq_of_parse_and_map(np, 1); + if (!irq_error) { + dev_err(&pdev->dev, "IRQ error missing or invalid\n"); + return -EINVAL; + } + + i2c_dev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(i2c_dev->clk)) { + dev_err(&pdev->dev, "Error: Missing controller clock\n"); + return PTR_ERR(i2c_dev->clk); + } + ret = clk_prepare_enable(i2c_dev->clk); + if (ret) { + dev_err(i2c_dev->dev, "Failed to prepare_enable clock\n"); + return ret; + } + + rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(rst)) { + dev_err(&pdev->dev, "Error: Missing controller reset\n"); + ret = PTR_ERR(rst); + goto clk_free; + } + reset_control_assert(rst); + udelay(2); + reset_control_deassert(rst); + + i2c_dev->speed = STM32F4_I2C_SPEED_STANDARD; + ret = of_property_read_u32(np, "clock-frequency", &clk_rate); + if (!ret && clk_rate >= 400000) + i2c_dev->speed = STM32F4_I2C_SPEED_FAST; + + i2c_dev->dev = &pdev->dev; + + ret = devm_request_irq(&pdev->dev, irq_event, stm32f4_i2c_isr_event, 0, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq event %i\n", + irq_event); + goto clk_free; + } + + ret = devm_request_irq(&pdev->dev, irq_error, stm32f4_i2c_isr_error, 0, + pdev->name, i2c_dev); + if (ret) { + dev_err(&pdev->dev, "Failed to request irq error %i\n", + irq_error); + goto clk_free; + } + + ret = stm32f4_i2c_hw_config(i2c_dev); + if (ret) + goto clk_free; + + adap = &i2c_dev->adap; + i2c_set_adapdata(adap, i2c_dev); + snprintf(adap->name, sizeof(adap->name), "STM32 I2C(%pa)", &res->start); + adap->owner = THIS_MODULE; + adap->timeout = 2 * HZ; + adap->retries = 0; + adap->algo = &stm32f4_i2c_algo; + adap->dev.parent = &pdev->dev; + adap->dev.of_node = pdev->dev.of_node; + + init_completion(&i2c_dev->complete); + + ret = i2c_add_adapter(adap); + if (ret) + goto clk_free; + + platform_set_drvdata(pdev, i2c_dev); + + clk_disable(i2c_dev->clk); + + dev_info(i2c_dev->dev, "STM32F4 I2C driver registered\n"); + + return 0; + +clk_free: + clk_disable_unprepare(i2c_dev->clk); + return ret; +} + +static int stm32f4_i2c_remove(struct platform_device *pdev) +{ + struct stm32f4_i2c_dev *i2c_dev = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c_dev->adap); + + clk_unprepare(i2c_dev->clk); + + return 0; +} + +static const struct of_device_id stm32f4_i2c_match[] = { + { .compatible = "st,stm32f4-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32f4_i2c_match); + +static struct platform_driver stm32f4_i2c_driver = { + .driver = { + .name = "stm32f4-i2c", + .of_match_table = stm32f4_i2c_match, + }, + .probe = stm32f4_i2c_probe, + .remove = stm32f4_i2c_remove, +}; + +module_platform_driver(stm32f4_i2c_driver); + +MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>"); +MODULE_DESCRIPTION("STMicroelectronics STM32F4 I2C driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-tegra-bpmp.c b/drivers/i2c/busses/i2c-tegra-bpmp.c new file mode 100644 index 000000000000..9eed69d5e17e --- /dev/null +++ b/drivers/i2c/busses/i2c-tegra-bpmp.c @@ -0,0 +1,346 @@ +/* + * drivers/i2c/busses/i2c-tegra-bpmp.c + * + * Copyright (c) 2016 NVIDIA Corporation. All rights reserved. + * + * Author: Shardar Shariff Md <smohammed@nvidia.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> + +#include <soc/tegra/bpmp-abi.h> +#include <soc/tegra/bpmp.h> + +/* + * Serialized I2C message header size is 6 bytes and includes address, flags + * and length + */ +#define SERIALI2C_HDR_SIZE 6 + +struct tegra_bpmp_i2c { + struct i2c_adapter adapter; + struct device *dev; + + struct tegra_bpmp *bpmp; + unsigned int bus; +}; + +/* + * Linux flags are translated to BPMP defined I2C flags that are used in BPMP + * firmware I2C driver to avoid any issues in future if Linux I2C flags are + * changed. + */ +static int tegra_bpmp_xlate_flags(u16 flags, u16 *out) +{ + if (flags & I2C_M_TEN) { + *out |= SERIALI2C_TEN; + flags &= ~I2C_M_TEN; + } + + if (flags & I2C_M_RD) { + *out |= SERIALI2C_RD; + flags &= ~I2C_M_RD; + } + + if (flags & I2C_M_STOP) { + *out |= SERIALI2C_STOP; + flags &= ~I2C_M_STOP; + } + + if (flags & I2C_M_NOSTART) { + *out |= SERIALI2C_NOSTART; + flags &= ~I2C_M_NOSTART; + } + + if (flags & I2C_M_REV_DIR_ADDR) { + *out |= SERIALI2C_REV_DIR_ADDR; + flags &= ~I2C_M_REV_DIR_ADDR; + } + + if (flags & I2C_M_IGNORE_NAK) { + *out |= SERIALI2C_IGNORE_NAK; + flags &= ~I2C_M_IGNORE_NAK; + } + + if (flags & I2C_M_NO_RD_ACK) { + *out |= SERIALI2C_NO_RD_ACK; + flags &= ~I2C_M_NO_RD_ACK; + } + + if (flags & I2C_M_RECV_LEN) { + *out |= SERIALI2C_RECV_LEN; + flags &= ~I2C_M_RECV_LEN; + } + + return (flags != 0) ? -EINVAL : 0; +} + +/** + * The serialized I2C format is simply the following: + * [addr little-endian][flags little-endian][len little-endian][data if write] + * [addr little-endian][flags little-endian][len little-endian][data if write] + * ... + * + * The flags are translated from Linux kernel representation to seriali2c + * representation. Any undefined flag being set causes an error. + * + * The data is there only for writes. Reads have the data transferred in the + * other direction, and thus data is not present. + * + * See deserialize_i2c documentation for the data format in the other direction. + */ +static int tegra_bpmp_serialize_i2c_msg(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_request *request, + struct i2c_msg *msgs, + unsigned int num) +{ + char *buf = request->xfer.data_buf; + unsigned int i, j, pos = 0; + int err; + + for (i = 0; i < num; i++) { + struct i2c_msg *msg = &msgs[i]; + u16 flags = 0; + + err = tegra_bpmp_xlate_flags(msg->flags, &flags); + if (err < 0) + return err; + + buf[pos++] = msg->addr & 0xff; + buf[pos++] = (msg->addr & 0xff00) >> 8; + buf[pos++] = flags & 0xff; + buf[pos++] = (flags & 0xff00) >> 8; + buf[pos++] = msg->len & 0xff; + buf[pos++] = (msg->len & 0xff00) >> 8; + + if ((flags & SERIALI2C_RD) == 0) { + for (j = 0; j < msg->len; j++) + buf[pos++] = msg->buf[j]; + } + } + + request->xfer.data_size = pos; + + return 0; +} + +/** + * The data in the BPMP -> CPU direction is composed of sequential blocks for + * those messages that have I2C_M_RD. So, for example, if you have: + * + * - !I2C_M_RD, len == 5, data == a0 01 02 03 04 + * - !I2C_M_RD, len == 1, data == a0 + * - I2C_M_RD, len == 2, data == [uninitialized buffer 1] + * - !I2C_M_RD, len == 1, data == a2 + * - I2C_M_RD, len == 2, data == [uninitialized buffer 2] + * + * ...then the data in the BPMP -> CPU direction would be 4 bytes total, and + * would contain 2 bytes that will go to uninitialized buffer 1, and 2 bytes + * that will go to uninitialized buffer 2. + */ +static int tegra_bpmp_i2c_deserialize(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_response *response, + struct i2c_msg *msgs, + unsigned int num) +{ + size_t size = response->xfer.data_size, len = 0, pos = 0; + char *buf = response->xfer.data_buf; + unsigned int i; + + for (i = 0; i < num; i++) + if (msgs[i].flags & I2C_M_RD) + len += msgs[i].len; + + if (len != size) + return -EINVAL; + + for (i = 0; i < num; i++) { + if (msgs[i].flags & I2C_M_RD) { + memcpy(msgs[i].buf, buf + pos, msgs[i].len); + pos += msgs[i].len; + } + } + + return 0; +} + +static int tegra_bpmp_i2c_msg_len_check(struct i2c_msg *msgs, unsigned int num) +{ + size_t tx_len = 0, rx_len = 0; + unsigned int i; + + for (i = 0; i < num; i++) + if (!(msgs[i].flags & I2C_M_RD)) + tx_len += SERIALI2C_HDR_SIZE + msgs[i].len; + + if (tx_len > TEGRA_I2C_IPC_MAX_IN_BUF_SIZE) + return -EINVAL; + + for (i = 0; i < num; i++) + if ((msgs[i].flags & I2C_M_RD)) + rx_len += msgs[i].len; + + if (rx_len > TEGRA_I2C_IPC_MAX_OUT_BUF_SIZE) + return -EINVAL; + + return 0; +} + +static int tegra_bpmp_i2c_msg_xfer(struct tegra_bpmp_i2c *i2c, + struct mrq_i2c_request *request, + struct mrq_i2c_response *response) +{ + struct tegra_bpmp_message msg; + int err; + + request->cmd = CMD_I2C_XFER; + request->xfer.bus_id = i2c->bus; + + memset(&msg, 0, sizeof(msg)); + msg.mrq = MRQ_I2C; + msg.tx.data = request; + msg.tx.size = sizeof(*request); + msg.rx.data = response; + msg.rx.size = sizeof(*response); + + if (irqs_disabled()) + err = tegra_bpmp_transfer_atomic(i2c->bpmp, &msg); + else + err = tegra_bpmp_transfer(i2c->bpmp, &msg); + + return err; +} + +static int tegra_bpmp_i2c_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + struct tegra_bpmp_i2c *i2c = i2c_get_adapdata(adapter); + struct mrq_i2c_response response; + struct mrq_i2c_request request; + int err; + + err = tegra_bpmp_i2c_msg_len_check(msgs, num); + if (err < 0) { + dev_err(i2c->dev, "unsupported message length\n"); + return err; + } + + memset(&request, 0, sizeof(request)); + memset(&response, 0, sizeof(response)); + + err = tegra_bpmp_serialize_i2c_msg(i2c, &request, msgs, num); + if (err < 0) { + dev_err(i2c->dev, "failed to serialize message: %d\n", err); + return err; + } + + err = tegra_bpmp_i2c_msg_xfer(i2c, &request, &response); + if (err < 0) { + dev_err(i2c->dev, "failed to transfer message: %d\n", err); + return err; + } + + err = tegra_bpmp_i2c_deserialize(i2c, &response, msgs, num); + if (err < 0) { + dev_err(i2c->dev, "failed to deserialize message: %d\n", err); + return err; + } + + return num; +} + +static u32 tegra_bpmp_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | + I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART; +} + +static const struct i2c_algorithm tegra_bpmp_i2c_algo = { + .master_xfer = tegra_bpmp_i2c_xfer, + .functionality = tegra_bpmp_i2c_func, +}; + +static int tegra_bpmp_i2c_probe(struct platform_device *pdev) +{ + struct tegra_bpmp_i2c *i2c; + u32 value; + int err; + + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->dev = &pdev->dev; + + i2c->bpmp = dev_get_drvdata(pdev->dev.parent); + if (!i2c->bpmp) + return -ENODEV; + + err = of_property_read_u32(pdev->dev.of_node, "nvidia,bpmp-bus-id", + &value); + if (err < 0) + return err; + + i2c->bus = value; + + i2c_set_adapdata(&i2c->adapter, i2c); + i2c->adapter.owner = THIS_MODULE; + strlcpy(i2c->adapter.name, "Tegra BPMP I2C adapter", + sizeof(i2c->adapter.name)); + i2c->adapter.algo = &tegra_bpmp_i2c_algo; + i2c->adapter.dev.parent = &pdev->dev; + i2c->adapter.dev.of_node = pdev->dev.of_node; + + platform_set_drvdata(pdev, i2c); + + return i2c_add_adapter(&i2c->adapter); +} + +static int tegra_bpmp_i2c_remove(struct platform_device *pdev) +{ + struct tegra_bpmp_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adapter); + + return 0; +} + +static const struct of_device_id tegra_bpmp_i2c_of_match[] = { + { .compatible = "nvidia,tegra186-bpmp-i2c", }, + { } +}; +MODULE_DEVICE_TABLE(of, tegra_bpmp_i2c_of_match); + +static struct platform_driver tegra_bpmp_i2c_driver = { + .driver = { + .name = "tegra-bpmp-i2c", + .of_match_table = tegra_bpmp_i2c_of_match, + }, + .probe = tegra_bpmp_i2c_probe, + .remove = tegra_bpmp_i2c_remove, +}; +module_platform_driver(tegra_bpmp_i2c_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra BPMP I2C bus contoller driver"); +MODULE_AUTHOR("Shardar Shariff Md <smohammed@nvidia.com>"); +MODULE_AUTHOR("Juha-Matti Tilli"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/i2c/busses/i2c-thunderx-pcidrv.c b/drivers/i2c/busses/i2c-thunderx-pcidrv.c index bba5b429f69c..1d4c2beacf2e 100644 --- a/drivers/i2c/busses/i2c-thunderx-pcidrv.c +++ b/drivers/i2c/busses/i2c-thunderx-pcidrv.c @@ -188,11 +188,11 @@ static int thunder_i2c_probe_pci(struct pci_dev *pdev, i2c->hlc_int_enable = thunder_i2c_hlc_int_enable; i2c->hlc_int_disable = thunder_i2c_hlc_int_disable; - ret = pci_enable_msix(pdev, &i2c->i2c_msix, 1); - if (ret) + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX); + if (ret < 0) goto error; - ret = devm_request_irq(dev, i2c->i2c_msix.vector, octeon_i2c_isr, 0, + ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), octeon_i2c_isr, 0, DRV_NAME, i2c); if (ret) goto error; diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c index 0ab1e55558bc..dbe7e44c9321 100644 --- a/drivers/i2c/busses/i2c-xgene-slimpro.c +++ b/drivers/i2c/busses/i2c-xgene-slimpro.c @@ -372,7 +372,7 @@ static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter) I2C_FUNC_SMBUS_I2C_BLOCK; } -static struct i2c_algorithm xgene_slimpro_i2c_algorithm = { +static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = { .smbus_xfer = xgene_slimpro_i2c_xfer, .functionality = xgene_slimpro_i2c_func, }; diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c index 84a8b2eccffb..66b464d52c9c 100644 --- a/drivers/i2c/busses/i2c-xlp9xx.c +++ b/drivers/i2c/busses/i2c-xlp9xx.c @@ -334,7 +334,7 @@ static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter) I2C_FUNC_10BIT_ADDR; } -static struct i2c_algorithm xlp9xx_i2c_algo = { +static const struct i2c_algorithm xlp9xx_i2c_algo = { .master_xfer = xlp9xx_i2c_xfer, .functionality = xlp9xx_i2c_functionality, }; diff --git a/drivers/i2c/busses/i2c-xlr.c b/drivers/i2c/busses/i2c-xlr.c index ad17d88d8573..484bfa15d58e 100644 --- a/drivers/i2c/busses/i2c-xlr.c +++ b/drivers/i2c/busses/i2c-xlr.c @@ -335,7 +335,7 @@ static u32 xlr_func(struct i2c_adapter *adap) return (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | I2C_FUNC_I2C; } -static struct i2c_algorithm xlr_i2c_algo = { +static const struct i2c_algorithm xlr_i2c_algo = { .master_xfer = xlr_i2c_xfer, .functionality = xlr_func, }; |