On Wed, Oct 07, 2009 at 11:38:15PM -0400, Mike Frysinger wrote: > From: Sonic Zhang <[email protected]> > > There isn't much point in managing our own custom timeout timer when the > completion interface already includes support for it. This makes the > resulting code much simpler and robust.
Looks like a candidate for next kernel release. > Signed-off-by: Sonic Zhang <[email protected]> > Signed-off-by: Mike Frysinger <[email protected]> > --- > drivers/i2c/busses/i2c-bfin-twi.c | 125 +++++++++++++++++++----------------- > 1 files changed, 66 insertions(+), 59 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-bfin-twi.c > b/drivers/i2c/busses/i2c-bfin-twi.c > index b309ac2..bbce6bd 100644 > --- a/drivers/i2c/busses/i2c-bfin-twi.c > +++ b/drivers/i2c/busses/i2c-bfin-twi.c > @@ -24,8 +24,6 @@ > #include <asm/portmux.h> > #include <asm/irq.h> > > -#define POLL_TIMEOUT (2 * HZ) > - > /* SMBus mode*/ > #define TWI_I2C_MODE_STANDARD 1 > #define TWI_I2C_MODE_STANDARDSUB 2 > @@ -43,8 +41,6 @@ struct bfin_twi_iface { > int cur_mode; > int manual_stop; > int result; > - int timeout_count; > - struct timer_list timeout_timer; > struct i2c_adapter adap; > struct completion complete; > struct i2c_msg *pmsg; > @@ -168,16 +164,13 @@ static void bfin_twi_handle_interrupt(struct > bfin_twi_iface *iface) > write_INT_MASK(iface, 0); > write_MASTER_CTL(iface, 0); > SSYNC(); > - /* If it is a quick transfer, only address bug no data, > + /* If it is a quick transfer, only address without data, > * not an err, return 1. > + * If address is acknowledged return 1. > */ > - if (iface->writeNum == 0 && (mast_stat & BUFRDERR)) > + if ((iface->writeNum == 0 && (mast_stat & BUFRDERR)) > + || !(mast_stat & ANAK)) > iface->result = 1; > - /* If address not acknowledged return -1, > - * else return 0. > - */ > - else if (!(mast_stat & ANAK)) > - iface->result = 0; > } > complete(&iface->complete); > return; > @@ -249,9 +242,9 @@ static void bfin_twi_handle_interrupt(struct > bfin_twi_iface *iface) > write_INT_MASK(iface, 0); > write_MASTER_CTL(iface, 0); > SSYNC(); > - complete(&iface->complete); > } > } > + complete(&iface->complete); > } > > /* Interrupt handler */ > @@ -261,36 +254,15 @@ static irqreturn_t bfin_twi_interrupt_entry(int irq, > void *dev_id) > unsigned long flags; > > spin_lock_irqsave(&iface->lock, flags); > - del_timer(&iface->timeout_timer); > bfin_twi_handle_interrupt(iface); > spin_unlock_irqrestore(&iface->lock, flags); > return IRQ_HANDLED; > } > > -static void bfin_twi_timeout(unsigned long data) > -{ > - struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data; > - unsigned long flags; > - > - spin_lock_irqsave(&iface->lock, flags); > - bfin_twi_handle_interrupt(iface); > - if (iface->result == 0) { > - iface->timeout_count--; > - if (iface->timeout_count > 0) { > - iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; > - add_timer(&iface->timeout_timer); > - } else { > - iface->result = -1; > - complete(&iface->complete); > - } > - } > - spin_unlock_irqrestore(&iface->lock, flags); > -} > - > /* > - * Generic i2c master transfer entrypoint > + * One i2c master transfer > */ > -static int bfin_twi_master_xfer(struct i2c_adapter *adap, > +static int bfin_twi_do_master_xfer(struct i2c_adapter *adap, > struct i2c_msg *msgs, int num) > { > struct bfin_twi_iface *iface = adap->algo_data; > @@ -318,7 +290,6 @@ static int bfin_twi_master_xfer(struct i2c_adapter *adap, > iface->transPtr = pmsg->buf; > iface->writeNum = iface->readNum = pmsg->len; > iface->result = 0; > - iface->timeout_count = 10; > init_completion(&(iface->complete)); > /* Set Transmit device address */ > write_MASTER_ADDR(iface, pmsg->addr); > @@ -357,30 +328,49 @@ static int bfin_twi_master_xfer(struct i2c_adapter > *adap, > iface->manual_stop = 1; > } > > - iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; > - add_timer(&iface->timeout_timer); > - > /* Master enable */ > write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN | > ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) | > ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0)); > SSYNC(); > > - wait_for_completion(&iface->complete); > - > - rc = iface->result; > + while (!iface->result) { > + if (!wait_for_completion_timeout(&iface->complete, > + adap->timeout * HZ)) { > + iface->result = -1; > + dev_err(&adap->dev, "master transfer timeout\n"); > + } > + } > > - if (rc == 1) > - return num; > + if (iface->result == 1) > + rc = iface->cur_msg + 1; > else > - return rc; > + rc = iface->result; > + > + return rc; > } > > /* > - * SMBus type transfer entrypoint > + * Generic i2c master transfer entrypoint > */ > +static int bfin_twi_master_xfer(struct i2c_adapter *adap, > + struct i2c_msg *msgs, int num) > +{ > + int i, ret = 0; > > -int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr, > + for (i = 0; i < adap->retries; i++) { > + ret = bfin_twi_do_master_xfer(adap, msgs, num); > + if (ret > 0) > + break; > + } > + > + return ret; > +} > + > +/* > + * One I2C SMBus transfer > + */ > +int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr, > unsigned short flags, char read_write, > u8 command, int size, union i2c_smbus_data *data) > { > @@ -468,7 +458,6 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 > addr, > iface->manual_stop = 0; > iface->read_write = read_write; > iface->command = command; > - iface->timeout_count = 10; > init_completion(&(iface->complete)); > > /* FIFO Initiation. Data in FIFO should be discarded before > @@ -485,9 +474,6 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 > addr, > write_MASTER_ADDR(iface, addr); > SSYNC(); > > - iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; > - add_timer(&iface->timeout_timer); > - > switch (iface->cur_mode) { > case TWI_I2C_MODE_STANDARDSUB: > write_XMT_DATA8(iface, iface->command); > @@ -549,10 +535,8 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 > addr, > else if (iface->readNum > 255) { > write_MASTER_CTL(iface, 0xff << 6); > iface->manual_stop = 1; > - } else { > - del_timer(&iface->timeout_timer); > + } else > break; > - } > } > } > write_INT_MASK(iface, MCOMP | MERR | > @@ -568,7 +552,13 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 > addr, > } > SSYNC(); > > - wait_for_completion(&iface->complete); > + while (!iface->result) { > + if (!wait_for_completion_timeout(&iface->complete, > + adap->timeout * HZ)) { > + iface->result = -1; > + dev_err(&adap->dev, "smbus transfer timeout\n"); > + } > + } > > rc = (iface->result >= 0) ? 0 : -1; > > @@ -576,6 +566,25 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 > addr, > } > > /* > + * Generic I2C SMBus transfer entrypoint > + */ > +int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr, > + unsigned short flags, char read_write, > + u8 command, int size, union i2c_smbus_data *data) > +{ > + int i, ret = 0; > + > + for (i = 0; i < adap->retries; i++) { > + ret = bfin_twi_do_smbus_xfer(adap, addr, flags, > + read_write, command, size, data); > + if (ret == 0) > + break; > + } > + > + return ret; > +} > + > +/* > * Return what the adapter supports > */ > static u32 bfin_twi_functionality(struct i2c_adapter *adap) > @@ -666,10 +675,6 @@ static int i2c_bfin_twi_probe(struct platform_device > *pdev) > goto out_error_no_irq; > } > > - init_timer(&(iface->timeout_timer)); > - iface->timeout_timer.function = bfin_twi_timeout; > - iface->timeout_timer.data = (unsigned long)iface; > - > p_adap = &iface->adap; > p_adap->nr = pdev->id; > strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name)); > @@ -677,6 +682,8 @@ static int i2c_bfin_twi_probe(struct platform_device > *pdev) > p_adap->algo_data = iface; > p_adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD; > p_adap->dev.parent = &pdev->dev; > + p_adap->timeout = 5; > + p_adap->retries = 3; > > rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi"); > if (rc) { > -- > 1.6.5.rc2 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Ben ([email protected], http://www.fluff.org/) 'a smiley only costs 4 bytes' -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
