diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-bfin-twi.c')
-rw-r--r-- | drivers/i2c/busses/i2c-bfin-twi.c | 147 |
1 files changed, 57 insertions, 90 deletions
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c index cdb59e5b23f7..0cf780fd6ef1 100644 --- a/drivers/i2c/busses/i2c-bfin-twi.c +++ b/drivers/i2c/busses/i2c-bfin-twi.c @@ -25,6 +25,7 @@ #include <asm/blackfin.h> #include <asm/portmux.h> #include <asm/irq.h> +#include <asm/bfin_twi.h> /* SMBus mode*/ #define TWI_I2C_MODE_STANDARD 1 @@ -32,56 +33,6 @@ #define TWI_I2C_MODE_COMBINED 3 #define TWI_I2C_MODE_REPEAT 4 -struct bfin_twi_iface { - int irq; - spinlock_t lock; - char read_write; - u8 command; - u8 *transPtr; - int readNum; - int writeNum; - int cur_mode; - int manual_stop; - int result; - struct i2c_adapter adap; - struct completion complete; - struct i2c_msg *pmsg; - int msg_num; - int cur_msg; - u16 saved_clkdiv; - u16 saved_control; - void __iomem *regs_base; -}; - - -#define DEFINE_TWI_REG(reg, off) \ -static inline u16 read_##reg(struct bfin_twi_iface *iface) \ - { return bfin_read16(iface->regs_base + (off)); } \ -static inline void write_##reg(struct bfin_twi_iface *iface, u16 v) \ - { bfin_write16(iface->regs_base + (off), v); } - -DEFINE_TWI_REG(CLKDIV, 0x00) -DEFINE_TWI_REG(CONTROL, 0x04) -DEFINE_TWI_REG(SLAVE_CTL, 0x08) -DEFINE_TWI_REG(SLAVE_STAT, 0x0C) -DEFINE_TWI_REG(SLAVE_ADDR, 0x10) -DEFINE_TWI_REG(MASTER_CTL, 0x14) -DEFINE_TWI_REG(MASTER_STAT, 0x18) -DEFINE_TWI_REG(MASTER_ADDR, 0x1C) -DEFINE_TWI_REG(INT_STAT, 0x20) -DEFINE_TWI_REG(INT_MASK, 0x24) -DEFINE_TWI_REG(FIFO_CTL, 0x28) -DEFINE_TWI_REG(FIFO_STAT, 0x2C) -DEFINE_TWI_REG(XMT_DATA8, 0x80) -DEFINE_TWI_REG(XMT_DATA16, 0x84) -DEFINE_TWI_REG(RCV_DATA8, 0x88) -DEFINE_TWI_REG(RCV_DATA16, 0x8C) - -static const u16 pin_req[2][3] = { - {P_TWI0_SCL, P_TWI0_SDA, 0}, - {P_TWI1_SCL, P_TWI1_SDA, 0}, -}; - static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, unsigned short twi_int_status) { @@ -99,7 +50,7 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, */ else if (iface->cur_mode == TWI_I2C_MODE_COMBINED) write_MASTER_CTL(iface, - read_MASTER_CTL(iface) | MDIR | RSTART); + read_MASTER_CTL(iface) | MDIR); else if (iface->manual_stop) write_MASTER_CTL(iface, read_MASTER_CTL(iface) | STOP); @@ -107,10 +58,10 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, iface->cur_msg + 1 < iface->msg_num) { if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD) write_MASTER_CTL(iface, - read_MASTER_CTL(iface) | RSTART | MDIR); + read_MASTER_CTL(iface) | MDIR); else write_MASTER_CTL(iface, - (read_MASTER_CTL(iface) | RSTART) & ~MDIR); + read_MASTER_CTL(iface) & ~MDIR); } } if (twi_int_status & RCVSERV) { @@ -130,17 +81,25 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, } iface->transPtr++; iface->readNum--; - } else if (iface->manual_stop) { - write_MASTER_CTL(iface, - read_MASTER_CTL(iface) | STOP); - } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT && - iface->cur_msg + 1 < iface->msg_num) { - if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD) - write_MASTER_CTL(iface, - read_MASTER_CTL(iface) | RSTART | MDIR); - else + } + + if (iface->readNum == 0) { + if (iface->manual_stop) { + /* Temporary workaround to avoid possible bus stall - + * Flush FIFO before issuing the STOP condition + */ + read_RCV_DATA16(iface); write_MASTER_CTL(iface, - (read_MASTER_CTL(iface) | RSTART) & ~MDIR); + read_MASTER_CTL(iface) | STOP); + } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT && + iface->cur_msg + 1 < iface->msg_num) { + if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD) + write_MASTER_CTL(iface, + read_MASTER_CTL(iface) | MDIR); + else + write_MASTER_CTL(iface, + read_MASTER_CTL(iface) & ~MDIR); + } } } if (twi_int_status & MERR) { @@ -193,7 +152,8 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, return; } if (twi_int_status & MCOMP) { - if ((read_MASTER_CTL(iface) & MEN) == 0 && + if (twi_int_status & (XMTSERV | RCVSERV) && + (read_MASTER_CTL(iface) & MEN) == 0 && (iface->cur_mode == TWI_I2C_MODE_REPEAT || iface->cur_mode == TWI_I2C_MODE_COMBINED)) { iface->result = -1; @@ -221,7 +181,7 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, write_MASTER_CTL(iface, read_MASTER_CTL(iface) & ~RSTART); } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT && - iface->cur_msg+1 < iface->msg_num) { + iface->cur_msg + 1 < iface->msg_num) { iface->cur_msg++; iface->transPtr = iface->pmsg[iface->cur_msg].buf; iface->writeNum = iface->readNum = @@ -241,27 +201,29 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, } } - if (iface->pmsg[iface->cur_msg].len <= 255) - write_MASTER_CTL(iface, + if (iface->pmsg[iface->cur_msg].len <= 255) { + write_MASTER_CTL(iface, (read_MASTER_CTL(iface) & (~(0xff << 6))) | - (iface->pmsg[iface->cur_msg].len << 6)); - else { + (iface->pmsg[iface->cur_msg].len << 6)); + iface->manual_stop = 0; + } else { write_MASTER_CTL(iface, (read_MASTER_CTL(iface) | (0xff << 6))); iface->manual_stop = 1; } - /* remove restart bit and enable master receive */ - write_MASTER_CTL(iface, - read_MASTER_CTL(iface) & ~RSTART); + /* remove restart bit before last message */ + if (iface->cur_msg + 1 == iface->msg_num) + write_MASTER_CTL(iface, + read_MASTER_CTL(iface) & ~RSTART); } else { iface->result = 1; write_INT_MASK(iface, 0); write_MASTER_CTL(iface, 0); } + complete(&iface->complete); } - complete(&iface->complete); } /* Interrupt handler */ @@ -298,8 +260,8 @@ static int bfin_twi_do_master_xfer(struct i2c_adapter *adap, if (!(read_CONTROL(iface) & TWI_ENA)) return -ENXIO; - while (read_MASTER_STAT(iface) & BUSBUSY) - yield(); + if (read_MASTER_STAT(iface) & BUSBUSY) + return -EAGAIN; iface->pmsg = msgs; iface->msg_num = num; @@ -311,7 +273,8 @@ static int bfin_twi_do_master_xfer(struct i2c_adapter *adap, return -EINVAL; } - iface->cur_mode = TWI_I2C_MODE_REPEAT; + if (iface->msg_num > 1) + iface->cur_mode = TWI_I2C_MODE_REPEAT; iface->manual_stop = 0; iface->transPtr = pmsg->buf; iface->writeNum = iface->readNum = pmsg->len; @@ -356,6 +319,7 @@ static int bfin_twi_do_master_xfer(struct i2c_adapter *adap, /* Master enable */ write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN | + (iface->msg_num > 1 ? RSTART : 0) | ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0)); SSYNC(); @@ -398,8 +362,8 @@ int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr, if (!(read_CONTROL(iface) & TWI_ENA)) return -ENXIO; - while (read_MASTER_STAT(iface) & BUSBUSY) - yield(); + if (read_MASTER_STAT(iface) & BUSBUSY) + return -EAGAIN; iface->writeNum = 0; iface->readNum = 0; @@ -520,7 +484,7 @@ int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr, else write_MASTER_CTL(iface, 0x1 << 6); /* Master enable */ - write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN | + write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN | RSTART | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0)); break; default: @@ -611,9 +575,9 @@ static struct i2c_algorithm bfin_twi_algorithm = { .functionality = bfin_twi_functionality, }; -static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state) +static int i2c_bfin_twi_suspend(struct device *dev) { - struct bfin_twi_iface *iface = platform_get_drvdata(pdev); + struct bfin_twi_iface *iface = dev_get_drvdata(dev); iface->saved_clkdiv = read_CLKDIV(iface); iface->saved_control = read_CONTROL(iface); @@ -626,14 +590,14 @@ static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state return 0; } -static int i2c_bfin_twi_resume(struct platform_device *pdev) +static int i2c_bfin_twi_resume(struct device *dev) { - struct bfin_twi_iface *iface = platform_get_drvdata(pdev); + struct bfin_twi_iface *iface = dev_get_drvdata(dev); int rc = request_irq(iface->irq, bfin_twi_interrupt_entry, - 0, pdev->name, iface); + 0, to_platform_device(dev)->name, iface); if (rc) { - dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq); + dev_err(dev, "Can't get IRQ %d !\n", iface->irq); return -ENODEV; } @@ -646,6 +610,9 @@ static int i2c_bfin_twi_resume(struct platform_device *pdev) return 0; } +static SIMPLE_DEV_PM_OPS(i2c_bfin_twi_pm, + i2c_bfin_twi_suspend, i2c_bfin_twi_resume); + static int i2c_bfin_twi_probe(struct platform_device *pdev) { struct bfin_twi_iface *iface; @@ -695,7 +662,8 @@ static int i2c_bfin_twi_probe(struct platform_device *pdev) p_adap->timeout = 5 * HZ; p_adap->retries = 3; - rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi"); + rc = peripheral_request_list((unsigned short *)pdev->dev.platform_data, + "i2c-bfin-twi"); if (rc) { dev_err(&pdev->dev, "Can't setup pin mux!\n"); goto out_error_pin_mux; @@ -742,7 +710,7 @@ out_error_add_adapter: free_irq(iface->irq, iface); out_error_req_irq: out_error_no_irq: - peripheral_free_list(pin_req[pdev->id]); + peripheral_free_list((unsigned short *)pdev->dev.platform_data); out_error_pin_mux: iounmap(iface->regs_base); out_error_ioremap: @@ -760,7 +728,7 @@ static int i2c_bfin_twi_remove(struct platform_device *pdev) i2c_del_adapter(&(iface->adap)); free_irq(iface->irq, iface); - peripheral_free_list(pin_req[pdev->id]); + peripheral_free_list((unsigned short *)pdev->dev.platform_data); iounmap(iface->regs_base); kfree(iface); @@ -770,11 +738,10 @@ static int i2c_bfin_twi_remove(struct platform_device *pdev) static struct platform_driver i2c_bfin_twi_driver = { .probe = i2c_bfin_twi_probe, .remove = i2c_bfin_twi_remove, - .suspend = i2c_bfin_twi_suspend, - .resume = i2c_bfin_twi_resume, .driver = { .name = "i2c-bfin-twi", .owner = THIS_MODULE, + .pm = &i2c_bfin_twi_pm, }, }; |