diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-pmcmsp.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-pmcmsp.c | 600 |
1 files changed, 0 insertions, 600 deletions
diff --git a/drivers/i2c/busses/i2c-pmcmsp.c b/drivers/i2c/busses/i2c-pmcmsp.c deleted file mode 100644 index 5d89c7c1b3a8..000000000000 --- a/drivers/i2c/busses/i2c-pmcmsp.c +++ /dev/null @@ -1,600 +0,0 @@ -/* - * Specific bus support for PMC-TWI compliant implementation on MSP71xx. - * - * Copyright 2005-2007 PMC-Sierra, Inc. - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation; either version 2 of the License, or (at your - * option) any later version. - * - * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED - * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN - * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF - * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON - * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/platform_device.h> -#include <linux/i2c.h> -#include <linux/interrupt.h> -#include <linux/completion.h> -#include <linux/mutex.h> -#include <linux/delay.h> -#include <linux/io.h> - -#define DRV_NAME "pmcmsptwi" - -#define MSP_TWI_SF_CLK_REG_OFFSET 0x00 -#define MSP_TWI_HS_CLK_REG_OFFSET 0x04 -#define MSP_TWI_CFG_REG_OFFSET 0x08 -#define MSP_TWI_CMD_REG_OFFSET 0x0c -#define MSP_TWI_ADD_REG_OFFSET 0x10 -#define MSP_TWI_DAT_0_REG_OFFSET 0x14 -#define MSP_TWI_DAT_1_REG_OFFSET 0x18 -#define MSP_TWI_INT_STS_REG_OFFSET 0x1c -#define MSP_TWI_INT_MSK_REG_OFFSET 0x20 -#define MSP_TWI_BUSY_REG_OFFSET 0x24 - -#define MSP_TWI_INT_STS_DONE (1 << 0) -#define MSP_TWI_INT_STS_LOST_ARBITRATION (1 << 1) -#define MSP_TWI_INT_STS_NO_RESPONSE (1 << 2) -#define MSP_TWI_INT_STS_DATA_COLLISION (1 << 3) -#define MSP_TWI_INT_STS_BUSY (1 << 4) -#define MSP_TWI_INT_STS_ALL 0x1f - -#define MSP_MAX_BYTES_PER_RW 8 -#define MSP_MAX_POLL 5 -#define MSP_POLL_DELAY 10 -#define MSP_IRQ_TIMEOUT (MSP_MAX_POLL * MSP_POLL_DELAY) - -/* IO Operation macros */ -#define pmcmsptwi_readl __raw_readl -#define pmcmsptwi_writel __raw_writel - -/* TWI command type */ -enum pmcmsptwi_cmd_type { - MSP_TWI_CMD_WRITE = 0, /* Write only */ - MSP_TWI_CMD_READ = 1, /* Read only */ - MSP_TWI_CMD_WRITE_READ = 2, /* Write then Read */ -}; - -/* The possible results of the xferCmd */ -enum pmcmsptwi_xfer_result { - MSP_TWI_XFER_OK = 0, - MSP_TWI_XFER_TIMEOUT, - MSP_TWI_XFER_BUSY, - MSP_TWI_XFER_DATA_COLLISION, - MSP_TWI_XFER_NO_RESPONSE, - MSP_TWI_XFER_LOST_ARBITRATION, -}; - -/* Corresponds to a PMCTWI clock configuration register */ -struct pmcmsptwi_clock { - u8 filter; /* Bits 15:12, default = 0x03 */ - u16 clock; /* Bits 9:0, default = 0x001f */ -}; - -struct pmcmsptwi_clockcfg { - struct pmcmsptwi_clock standard; /* The standard/fast clock config */ - struct pmcmsptwi_clock highspeed; /* The highspeed clock config */ -}; - -/* Corresponds to the main TWI configuration register */ -struct pmcmsptwi_cfg { - u8 arbf; /* Bits 15:12, default=0x03 */ - u8 nak; /* Bits 11:8, default=0x03 */ - u8 add10; /* Bit 7, default=0x00 */ - u8 mst_code; /* Bits 6:4, default=0x00 */ - u8 arb; /* Bit 1, default=0x01 */ - u8 highspeed; /* Bit 0, default=0x00 */ -}; - -/* A single pmctwi command to issue */ -struct pmcmsptwi_cmd { - u16 addr; /* The slave address (7 or 10 bits) */ - enum pmcmsptwi_cmd_type type; /* The command type */ - u8 write_len; /* Number of bytes in the write buffer */ - u8 read_len; /* Number of bytes in the read buffer */ - u8 *write_data; /* Buffer of characters to send */ - u8 *read_data; /* Buffer to fill with incoming data */ -}; - -/* The private data */ -struct pmcmsptwi_data { - void __iomem *iobase; /* iomapped base for IO */ - int irq; /* IRQ to use (0 disables) */ - struct completion wait; /* Completion for xfer */ - struct mutex lock; /* Used for threadsafeness */ - enum pmcmsptwi_xfer_result last_result; /* result of last xfer */ -}; - -/* The default settings */ -static const struct pmcmsptwi_clockcfg pmcmsptwi_defclockcfg = { - .standard = { - .filter = 0x3, - .clock = 0x1f, - }, - .highspeed = { - .filter = 0x3, - .clock = 0x1f, - }, -}; - -static const struct pmcmsptwi_cfg pmcmsptwi_defcfg = { - .arbf = 0x03, - .nak = 0x03, - .add10 = 0x00, - .mst_code = 0x00, - .arb = 0x01, - .highspeed = 0x00, -}; - -static struct pmcmsptwi_data pmcmsptwi_data; - -static struct i2c_adapter pmcmsptwi_adapter; - -/* inline helper functions */ -static inline u32 pmcmsptwi_clock_to_reg( - const struct pmcmsptwi_clock *clock) -{ - return ((clock->filter & 0xf) << 12) | (clock->clock & 0x03ff); -} - -static inline u32 pmcmsptwi_cfg_to_reg(const struct pmcmsptwi_cfg *cfg) -{ - return ((cfg->arbf & 0xf) << 12) | - ((cfg->nak & 0xf) << 8) | - ((cfg->add10 & 0x1) << 7) | - ((cfg->mst_code & 0x7) << 4) | - ((cfg->arb & 0x1) << 1) | - (cfg->highspeed & 0x1); -} - -static inline void pmcmsptwi_reg_to_cfg(u32 reg, struct pmcmsptwi_cfg *cfg) -{ - cfg->arbf = (reg >> 12) & 0xf; - cfg->nak = (reg >> 8) & 0xf; - cfg->add10 = (reg >> 7) & 0x1; - cfg->mst_code = (reg >> 4) & 0x7; - cfg->arb = (reg >> 1) & 0x1; - cfg->highspeed = reg & 0x1; -} - -/* - * Sets the current clock configuration - */ -static void pmcmsptwi_set_clock_config(const struct pmcmsptwi_clockcfg *cfg, - struct pmcmsptwi_data *data) -{ - mutex_lock(&data->lock); - pmcmsptwi_writel(pmcmsptwi_clock_to_reg(&cfg->standard), - data->iobase + MSP_TWI_SF_CLK_REG_OFFSET); - pmcmsptwi_writel(pmcmsptwi_clock_to_reg(&cfg->highspeed), - data->iobase + MSP_TWI_HS_CLK_REG_OFFSET); - mutex_unlock(&data->lock); -} - -/* - * Gets the current TWI bus configuration - */ -static void pmcmsptwi_get_twi_config(struct pmcmsptwi_cfg *cfg, - struct pmcmsptwi_data *data) -{ - mutex_lock(&data->lock); - pmcmsptwi_reg_to_cfg(pmcmsptwi_readl( - data->iobase + MSP_TWI_CFG_REG_OFFSET), cfg); - mutex_unlock(&data->lock); -} - -/* - * Sets the current TWI bus configuration - */ -static void pmcmsptwi_set_twi_config(const struct pmcmsptwi_cfg *cfg, - struct pmcmsptwi_data *data) -{ - mutex_lock(&data->lock); - pmcmsptwi_writel(pmcmsptwi_cfg_to_reg(cfg), - data->iobase + MSP_TWI_CFG_REG_OFFSET); - mutex_unlock(&data->lock); -} - -/* - * Parses the 'int_sts' register and returns a well-defined error code - */ -static enum pmcmsptwi_xfer_result pmcmsptwi_get_result(u32 reg) -{ - if (reg & MSP_TWI_INT_STS_LOST_ARBITRATION) { - dev_dbg(&pmcmsptwi_adapter.dev, - "Result: Lost arbitration\n"); - return MSP_TWI_XFER_LOST_ARBITRATION; - } else if (reg & MSP_TWI_INT_STS_NO_RESPONSE) { - dev_dbg(&pmcmsptwi_adapter.dev, - "Result: No response\n"); - return MSP_TWI_XFER_NO_RESPONSE; - } else if (reg & MSP_TWI_INT_STS_DATA_COLLISION) { - dev_dbg(&pmcmsptwi_adapter.dev, - "Result: Data collision\n"); - return MSP_TWI_XFER_DATA_COLLISION; - } else if (reg & MSP_TWI_INT_STS_BUSY) { - dev_dbg(&pmcmsptwi_adapter.dev, - "Result: Bus busy\n"); - return MSP_TWI_XFER_BUSY; - } - - dev_dbg(&pmcmsptwi_adapter.dev, "Result: Operation succeeded\n"); - return MSP_TWI_XFER_OK; -} - -/* - * In interrupt mode, handle the interrupt. - * NOTE: Assumes data->lock is held. - */ -static irqreturn_t pmcmsptwi_interrupt(int irq, void *ptr) -{ - struct pmcmsptwi_data *data = ptr; - - u32 reason = pmcmsptwi_readl(data->iobase + - MSP_TWI_INT_STS_REG_OFFSET); - pmcmsptwi_writel(reason, data->iobase + MSP_TWI_INT_STS_REG_OFFSET); - - dev_dbg(&pmcmsptwi_adapter.dev, "Got interrupt 0x%08x\n", reason); - if (!(reason & MSP_TWI_INT_STS_DONE)) - return IRQ_NONE; - - data->last_result = pmcmsptwi_get_result(reason); - complete(&data->wait); - - return IRQ_HANDLED; -} - -/* - * Probe for and register the device and return 0 if there is one. - */ -static int pmcmsptwi_probe(struct platform_device *pldev) -{ - struct resource *res; - int rc = -ENODEV; - - /* get the static platform resources */ - res = platform_get_resource(pldev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(&pldev->dev, "IOMEM resource not found\n"); - goto ret_err; - } - - /* reserve the memory region */ - if (!request_mem_region(res->start, resource_size(res), - pldev->name)) { - dev_err(&pldev->dev, - "Unable to get memory/io address region %pap\n", - &res->start); - rc = -EBUSY; - goto ret_err; - } - - /* remap the memory */ - pmcmsptwi_data.iobase = ioremap(res->start, - resource_size(res)); - if (!pmcmsptwi_data.iobase) { - dev_err(&pldev->dev, - "Unable to ioremap address %pap\n", &res->start); - rc = -EIO; - goto ret_unreserve; - } - - /* request the irq */ - pmcmsptwi_data.irq = platform_get_irq(pldev, 0); - if (pmcmsptwi_data.irq) { - rc = request_irq(pmcmsptwi_data.irq, &pmcmsptwi_interrupt, - IRQF_SHARED, pldev->name, &pmcmsptwi_data); - if (rc == 0) { - /* - * Enable 'DONE' interrupt only. - * - * If you enable all interrupts, you will get one on - * error and another when the operation completes. - * This way you only have to handle one interrupt, - * but you can still check all result flags. - */ - pmcmsptwi_writel(MSP_TWI_INT_STS_DONE, - pmcmsptwi_data.iobase + - MSP_TWI_INT_MSK_REG_OFFSET); - } else { - dev_warn(&pldev->dev, - "Could not assign TWI IRQ handler " - "to irq %d (continuing with poll)\n", - pmcmsptwi_data.irq); - pmcmsptwi_data.irq = 0; - } - } - - init_completion(&pmcmsptwi_data.wait); - mutex_init(&pmcmsptwi_data.lock); - - pmcmsptwi_set_clock_config(&pmcmsptwi_defclockcfg, &pmcmsptwi_data); - pmcmsptwi_set_twi_config(&pmcmsptwi_defcfg, &pmcmsptwi_data); - - printk(KERN_INFO DRV_NAME ": Registering MSP71xx I2C adapter\n"); - - pmcmsptwi_adapter.dev.parent = &pldev->dev; - platform_set_drvdata(pldev, &pmcmsptwi_adapter); - i2c_set_adapdata(&pmcmsptwi_adapter, &pmcmsptwi_data); - - rc = i2c_add_adapter(&pmcmsptwi_adapter); - if (rc) - goto ret_unmap; - - return 0; - -ret_unmap: - if (pmcmsptwi_data.irq) { - pmcmsptwi_writel(0, - pmcmsptwi_data.iobase + MSP_TWI_INT_MSK_REG_OFFSET); - free_irq(pmcmsptwi_data.irq, &pmcmsptwi_data); - } - - iounmap(pmcmsptwi_data.iobase); - -ret_unreserve: - release_mem_region(res->start, resource_size(res)); - -ret_err: - return rc; -} - -/* - * Release the device and return 0 if there is one. - */ -static int pmcmsptwi_remove(struct platform_device *pldev) -{ - struct resource *res; - - i2c_del_adapter(&pmcmsptwi_adapter); - - if (pmcmsptwi_data.irq) { - pmcmsptwi_writel(0, - pmcmsptwi_data.iobase + MSP_TWI_INT_MSK_REG_OFFSET); - free_irq(pmcmsptwi_data.irq, &pmcmsptwi_data); - } - - iounmap(pmcmsptwi_data.iobase); - - res = platform_get_resource(pldev, IORESOURCE_MEM, 0); - release_mem_region(res->start, resource_size(res)); - - return 0; -} - -/* - * Polls the 'busy' register until the command is complete. - * NOTE: Assumes data->lock is held. - */ -static void pmcmsptwi_poll_complete(struct pmcmsptwi_data *data) -{ - int i; - - for (i = 0; i < MSP_MAX_POLL; i++) { - u32 val = pmcmsptwi_readl(data->iobase + - MSP_TWI_BUSY_REG_OFFSET); - if (val == 0) { - u32 reason = pmcmsptwi_readl(data->iobase + - MSP_TWI_INT_STS_REG_OFFSET); - pmcmsptwi_writel(reason, data->iobase + - MSP_TWI_INT_STS_REG_OFFSET); - data->last_result = pmcmsptwi_get_result(reason); - return; - } - udelay(MSP_POLL_DELAY); - } - - dev_dbg(&pmcmsptwi_adapter.dev, "Result: Poll timeout\n"); - data->last_result = MSP_TWI_XFER_TIMEOUT; -} - -/* - * Do the transfer (low level): - * May use interrupt-driven or polling, depending on if an IRQ is - * presently registered. - * NOTE: Assumes data->lock is held. - */ -static enum pmcmsptwi_xfer_result pmcmsptwi_do_xfer( - u32 reg, struct pmcmsptwi_data *data) -{ - dev_dbg(&pmcmsptwi_adapter.dev, "Writing cmd reg 0x%08x\n", reg); - pmcmsptwi_writel(reg, data->iobase + MSP_TWI_CMD_REG_OFFSET); - if (data->irq) { - unsigned long timeleft = wait_for_completion_timeout( - &data->wait, MSP_IRQ_TIMEOUT); - if (timeleft == 0) { - dev_dbg(&pmcmsptwi_adapter.dev, - "Result: IRQ timeout\n"); - complete(&data->wait); - data->last_result = MSP_TWI_XFER_TIMEOUT; - } - } else - pmcmsptwi_poll_complete(data); - - return data->last_result; -} - -/* - * Helper routine, converts 'pmctwi_cmd' struct to register format - */ -static inline u32 pmcmsptwi_cmd_to_reg(const struct pmcmsptwi_cmd *cmd) -{ - return ((cmd->type & 0x3) << 8) | - (((cmd->write_len - 1) & 0x7) << 4) | - ((cmd->read_len - 1) & 0x7); -} - -/* - * Do the transfer (high level) - */ -static enum pmcmsptwi_xfer_result pmcmsptwi_xfer_cmd( - struct pmcmsptwi_cmd *cmd, - struct pmcmsptwi_data *data) -{ - enum pmcmsptwi_xfer_result retval; - - mutex_lock(&data->lock); - dev_dbg(&pmcmsptwi_adapter.dev, - "Setting address to 0x%04x\n", cmd->addr); - pmcmsptwi_writel(cmd->addr, data->iobase + MSP_TWI_ADD_REG_OFFSET); - - if (cmd->type == MSP_TWI_CMD_WRITE || - cmd->type == MSP_TWI_CMD_WRITE_READ) { - u64 tmp = be64_to_cpup((__be64 *)cmd->write_data); - tmp >>= (MSP_MAX_BYTES_PER_RW - cmd->write_len) * 8; - dev_dbg(&pmcmsptwi_adapter.dev, "Writing 0x%016llx\n", tmp); - pmcmsptwi_writel(tmp & 0x00000000ffffffffLL, - data->iobase + MSP_TWI_DAT_0_REG_OFFSET); - if (cmd->write_len > 4) - pmcmsptwi_writel(tmp >> 32, - data->iobase + MSP_TWI_DAT_1_REG_OFFSET); - } - - retval = pmcmsptwi_do_xfer(pmcmsptwi_cmd_to_reg(cmd), data); - if (retval != MSP_TWI_XFER_OK) - goto xfer_err; - - if (cmd->type == MSP_TWI_CMD_READ || - cmd->type == MSP_TWI_CMD_WRITE_READ) { - int i; - u64 rmsk = ~(0xffffffffffffffffLL << (cmd->read_len * 8)); - u64 tmp = (u64)pmcmsptwi_readl(data->iobase + - MSP_TWI_DAT_0_REG_OFFSET); - if (cmd->read_len > 4) - tmp |= (u64)pmcmsptwi_readl(data->iobase + - MSP_TWI_DAT_1_REG_OFFSET) << 32; - tmp &= rmsk; - dev_dbg(&pmcmsptwi_adapter.dev, "Read 0x%016llx\n", tmp); - - for (i = 0; i < cmd->read_len; i++) - cmd->read_data[i] = tmp >> i; - } - -xfer_err: - mutex_unlock(&data->lock); - - return retval; -} - -/* -- Algorithm functions -- */ - -/* - * Sends an i2c command out on the adapter - */ -static int pmcmsptwi_master_xfer(struct i2c_adapter *adap, - struct i2c_msg *msg, int num) -{ - struct pmcmsptwi_data *data = i2c_get_adapdata(adap); - struct pmcmsptwi_cmd cmd; - struct pmcmsptwi_cfg oldcfg, newcfg; - int ret; - - if (num == 2) { - struct i2c_msg *nextmsg = msg + 1; - - cmd.type = MSP_TWI_CMD_WRITE_READ; - cmd.write_len = msg->len; - cmd.write_data = msg->buf; - cmd.read_len = nextmsg->len; - cmd.read_data = nextmsg->buf; - } else if (msg->flags & I2C_M_RD) { - cmd.type = MSP_TWI_CMD_READ; - cmd.read_len = msg->len; - cmd.read_data = msg->buf; - cmd.write_len = 0; - cmd.write_data = NULL; - } else { - cmd.type = MSP_TWI_CMD_WRITE; - cmd.read_len = 0; - cmd.read_data = NULL; - cmd.write_len = msg->len; - cmd.write_data = msg->buf; - } - - cmd.addr = msg->addr; - - if (msg->flags & I2C_M_TEN) { - pmcmsptwi_get_twi_config(&newcfg, data); - memcpy(&oldcfg, &newcfg, sizeof(oldcfg)); - - /* Set the special 10-bit address flag */ - newcfg.add10 = 1; - - pmcmsptwi_set_twi_config(&newcfg, data); - } - - /* Execute the command */ - ret = pmcmsptwi_xfer_cmd(&cmd, data); - - if (msg->flags & I2C_M_TEN) - pmcmsptwi_set_twi_config(&oldcfg, data); - - dev_dbg(&adap->dev, "I2C %s of %d bytes %s\n", - (msg->flags & I2C_M_RD) ? "read" : "write", msg->len, - (ret == MSP_TWI_XFER_OK) ? "succeeded" : "failed"); - - if (ret != MSP_TWI_XFER_OK) { - /* - * TODO: We could potentially loop and retry in the case - * of MSP_TWI_XFER_TIMEOUT. - */ - return -EIO; - } - - return num; -} - -static u32 pmcmsptwi_i2c_func(struct i2c_adapter *adapter) -{ - return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | - I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | - I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_PROC_CALL; -} - -static const struct i2c_adapter_quirks pmcmsptwi_i2c_quirks = { - .flags = I2C_AQ_COMB_WRITE_THEN_READ | I2C_AQ_NO_ZERO_LEN, - .max_write_len = MSP_MAX_BYTES_PER_RW, - .max_read_len = MSP_MAX_BYTES_PER_RW, - .max_comb_1st_msg_len = MSP_MAX_BYTES_PER_RW, - .max_comb_2nd_msg_len = MSP_MAX_BYTES_PER_RW, -}; - -/* -- Initialization -- */ - -static const struct i2c_algorithm pmcmsptwi_algo = { - .master_xfer = pmcmsptwi_master_xfer, - .functionality = pmcmsptwi_i2c_func, -}; - -static struct i2c_adapter pmcmsptwi_adapter = { - .owner = THIS_MODULE, - .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, - .algo = &pmcmsptwi_algo, - .quirks = &pmcmsptwi_i2c_quirks, - .name = DRV_NAME, -}; - -static struct platform_driver pmcmsptwi_driver = { - .probe = pmcmsptwi_probe, - .remove = pmcmsptwi_remove, - .driver = { - .name = DRV_NAME, - }, -}; - -module_platform_driver(pmcmsptwi_driver); - -MODULE_DESCRIPTION("PMC MSP TWI/SMBus/I2C driver"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:" DRV_NAME); |