On Tue, 24 Feb 2009 17:22:15 +0100, Wolfram Sang wrote: > We now timeout also if the state machine does not change within the > given time. For that, the driver-specific completion-functions are > extended to return true or false depending on the timeout. This then > gets checked in the algorithm. > > Signed-off-by: Wolfram Sang <[email protected]> > --- > drivers/i2c/algos/i2c-algo-pca.c | 39 +++++++++++++++++--------------- > drivers/i2c/busses/i2c-pca-isa.c | 18 +++++++++++---- > drivers/i2c/busses/i2c-pca-platform.c | 20 ++++++++-------- > 3 files changed, 44 insertions(+), 33 deletions(-) > > diff --git a/drivers/i2c/algos/i2c-algo-pca.c > b/drivers/i2c/algos/i2c-algo-pca.c > index 59ee88a..4153aff 100644 > --- a/drivers/i2c/algos/i2c-algo-pca.c > +++ b/drivers/i2c/algos/i2c-algo-pca.c > @@ -60,14 +60,14 @@ static void pca9665_reset(void *pd) > * > * returns after the start condition has occurred > */ > -static void pca_start(struct i2c_algo_pca_data *adap) > +static int pca_start(struct i2c_algo_pca_data *adap) > { > int sta = pca_get_con(adap); > DEB2("=== START\n"); > sta |= I2C_PCA_CON_STA; > sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); > pca_set_con(adap, sta); > - pca_wait(adap); > + return pca_wait(adap); > } > > /* > @@ -75,14 +75,14 @@ static void pca_start(struct i2c_algo_pca_data *adap) > * > * return after the repeated start condition has occurred > */ > -static void pca_repeated_start(struct i2c_algo_pca_data *adap) > +static int pca_repeated_start(struct i2c_algo_pca_data *adap) > { > int sta = pca_get_con(adap); > DEB2("=== REPEATED START\n"); > sta |= I2C_PCA_CON_STA; > sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_SI); > pca_set_con(adap, sta); > - pca_wait(adap); > + return pca_wait(adap); > } > > /* > @@ -108,7 +108,7 @@ static void pca_stop(struct i2c_algo_pca_data *adap) > * > * returns after the address has been sent > */ > -static void pca_address(struct i2c_algo_pca_data *adap, > +static int pca_address(struct i2c_algo_pca_data *adap, > struct i2c_msg *msg) > { > int sta = pca_get_con(adap); > @@ -125,7 +125,7 @@ static void pca_address(struct i2c_algo_pca_data *adap, > sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); > pca_set_con(adap, sta); > > - pca_wait(adap); > + return pca_wait(adap); > } > > /* > @@ -133,7 +133,7 @@ static void pca_address(struct i2c_algo_pca_data *adap, > * > * Returns after the byte has been transmitted > */ > -static void pca_tx_byte(struct i2c_algo_pca_data *adap, > +static int pca_tx_byte(struct i2c_algo_pca_data *adap, > __u8 b) > { > int sta = pca_get_con(adap); > @@ -143,7 +143,7 @@ static void pca_tx_byte(struct i2c_algo_pca_data *adap, > sta &= ~(I2C_PCA_CON_STO|I2C_PCA_CON_STA|I2C_PCA_CON_SI); > pca_set_con(adap, sta); > > - pca_wait(adap); > + return pca_wait(adap); > } > > /* > @@ -163,7 +163,7 @@ static void pca_rx_byte(struct i2c_algo_pca_data *adap, > * > * Returns after next byte has arrived. > */ > -static void pca_rx_ack(struct i2c_algo_pca_data *adap, > +static int pca_rx_ack(struct i2c_algo_pca_data *adap, > int ack) > { > int sta = pca_get_con(adap); > @@ -174,7 +174,7 @@ static void pca_rx_ack(struct i2c_algo_pca_data *adap, > sta |= I2C_PCA_CON_AA; > > pca_set_con(adap, sta); > - pca_wait(adap); > + return pca_wait(adap); > } > > static int pca_xfer(struct i2c_adapter *i2c_adap, > @@ -187,6 +187,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > int numbytes = 0; > int state; > int ret; > + int completed = 1; > unsigned long timeout = jiffies + i2c_adap->timeout; > > while (pca_status(adap) != 0xf8) { > @@ -231,18 +232,18 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > > switch (state) { > case 0xf8: /* On reset or stop the bus is idle */ > - pca_start(adap); > + completed = pca_start(adap); > break; > > case 0x08: /* A START condition has been transmitted */ > case 0x10: /* A repeated start condition has been transmitted */ > - pca_address(adap, msg); > + completed = pca_address(adap, msg); > break; > > case 0x18: /* SLA+W has been transmitted; ACK has been received > */ > case 0x28: /* Data byte in I2CDAT has been transmitted; ACK has > been received */ > if (numbytes < msg->len) { > - pca_tx_byte(adap, msg->buf[numbytes]); > + completed = pca_tx_byte(adap, > msg->buf[numbytes]); > numbytes++; > break; > } > @@ -250,7 +251,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > if (curmsg == num) > pca_stop(adap); > else > - pca_repeated_start(adap); > + completed = pca_repeated_start(adap); > break; > > case 0x20: /* SLA+W has been transmitted; NOT ACK has been > received */ > @@ -259,21 +260,21 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > goto out; > > case 0x40: /* SLA+R has been transmitted; ACK has been received > */ > - pca_rx_ack(adap, msg->len > 1); > + completed = pca_rx_ack(adap, msg->len > 1); > break; > > case 0x50: /* Data bytes has been received; ACK has been > returned */ > if (numbytes < msg->len) { > pca_rx_byte(adap, &msg->buf[numbytes], 1); > numbytes++; > - pca_rx_ack(adap, numbytes < msg->len - 1); > + completed = pca_rx_ack(adap, numbytes < > msg->len - 1); > break; > } > curmsg++; numbytes = 0; > if (curmsg == num) > pca_stop(adap); > else > - pca_repeated_start(adap); > + completed = pca_repeated_start(adap); > break; > > case 0x48: /* SLA+R has been transmitted; NOT ACK has been > received */ > @@ -296,7 +297,7 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > if (curmsg == num) > pca_stop(adap); > else > - pca_repeated_start(adap); > + completed = pca_repeated_start(adap); > } else { > DEB2("NOT ACK sent after data byte received. " > "Not final byte. numbytes %d. len %d\n", > @@ -322,6 +323,8 @@ static int pca_xfer(struct i2c_adapter *i2c_adap, > break; > } > > + if (!completed) > + goto out; > } > > ret = curmsg; > diff --git a/drivers/i2c/busses/i2c-pca-isa.c > b/drivers/i2c/busses/i2c-pca-isa.c > index 84d035c..a523be8 100644 > --- a/drivers/i2c/busses/i2c-pca-isa.c > +++ b/drivers/i2c/busses/i2c-pca-isa.c > @@ -23,6 +23,7 @@ > #include <linux/module.h> > #include <linux/moduleparam.h> > #include <linux/delay.h> > +#include <linux/jiffies.h> > #include <linux/init.h> > #include <linux/interrupt.h> > #include <linux/wait.h> > @@ -43,6 +44,7 @@ static int irq = -1; > * in the actual clock rate */ > static int clock = 59000; > > +static struct i2c_adapter pca_isa_ops; > static wait_queue_head_t pca_wait; > > static void pca_isa_writebyte(void *pd, int reg, int val) > @@ -68,16 +70,22 @@ static int pca_isa_readbyte(void *pd, int reg) > > static int pca_isa_waitforcompletion(void *pd) > { > - int ret = 0; > + long ret = ~0; > + unsigned long timeout; > > if (irq > -1) { > - ret = wait_event_interruptible(pca_wait, > - pca_isa_readbyte(pd, > I2C_PCA_CON) & I2C_PCA_CON_SI); > + ret = wait_event_interruptible_timeout(pca_wait, > + pca_isa_readbyte(pd, I2C_PCA_CON) > + & I2C_PCA_CON_SI, pca_isa_ops.timeout); > } else { > - while ((pca_isa_readbyte(pd, I2C_PCA_CON) & I2C_PCA_CON_SI) == > 0) > + /* Do polling */ > + timeout = jiffies + pca_isa_ops.timeout; > + while (((pca_isa_readbyte(pd, I2C_PCA_CON) > + & I2C_PCA_CON_SI) == 0) > + && (ret = time_before(jiffies, timeout))) > udelay(100); > } > - return ret; > + return ret > 0; > } > > static void pca_isa_resetchip(void *pd) > diff --git a/drivers/i2c/busses/i2c-pca-platform.c > b/drivers/i2c/busses/i2c-pca-platform.c > index 51d179b..df5e593 100644 > --- a/drivers/i2c/busses/i2c-pca-platform.c > +++ b/drivers/i2c/busses/i2c-pca-platform.c > @@ -15,6 +15,7 @@ > #include <linux/init.h> > #include <linux/slab.h> > #include <linux/delay.h> > +#include <linux/jiffies.h> > #include <linux/errno.h> > #include <linux/i2c.h> > #include <linux/interrupt.h> > @@ -81,24 +82,23 @@ static void i2c_pca_pf_writebyte32(void *pd, int reg, int > val) > static int i2c_pca_pf_waitforcompletion(void *pd) > { > struct i2c_pca_pf_data *i2c = pd; > - int ret = 0; > + long ret = ~0; > + unsigned long timeout; > > if (i2c->irq) { > - ret = wait_event_interruptible(i2c->wait, > + ret = wait_event_interruptible_timeout(i2c->wait, > i2c->algo_data.read_byte(i2c, I2C_PCA_CON) > - & I2C_PCA_CON_SI); > + & I2C_PCA_CON_SI, i2c->adap.timeout); > } else { > - /* > - * Do polling... > - * XXX: Could get stuck in extreme cases! > - * Maybe add timeout, but using irqs is preferred anyhow. > - */ > - while ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) > + /* Do polling */ > + timeout = jiffies + i2c->adap.timeout; > + while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) > & I2C_PCA_CON_SI) == 0) > + && (ret = time_before(jiffies, timeout))) > udelay(100); > } > > - return ret; > + return ret > 0; > } > > static void i2c_pca_pf_dummyreset(void *pd)
Looks good. Applied, thanks. -- Jean Delvare -- 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
