From a804644a1a31a0b85e4c7d3c49f30419513cb6c1 Mon Sep 17 00:00:00 2001 From: Mike Ditto Date: Tue, 16 Dec 2008 20:17:09 +0000 Subject: i2c-cpm: Detect and report NAK right away instead of timing out Make the driver report an ENXIO error immediately upon NAK instead of waiting for another interrupt and getting a timeout. When reading from a device that is not present or declines to respond to, e.g., a non-existent register address, CPM immediately reports a NAK condition in the TxBD, but the driver kept waiting until a timeout, which takes 1 second and causes an ugly console error message. Signed-off-by: Mike Ditto Acked-by: Jochen Friedrich [ben-linux@fluff.org: reordered description text] Signed-off-by: Ben Dooks diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c index 228f757..3fcf78e 100644 --- a/drivers/i2c/busses/i2c-cpm.c +++ b/drivers/i2c/busses/i2c-cpm.c @@ -365,6 +365,7 @@ static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) pmsg = &msgs[tptr]; if (pmsg->flags & I2C_M_RD) ret = wait_event_interruptible_timeout(cpm->i2c_wait, + (in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) || !(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY), 1 * HZ); else -- cgit v0.10.2 From be44f01e8af3862767f466f89c12640a2f2b0038 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Fri, 31 Oct 2008 16:10:22 +0000 Subject: i2c-s3c2410: fix check for being in suspend. As noted by Julia Lawall , we can never trigger the check for being in suspend due to the result of !readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN always being 0. Add suspend/resume hooks to stop i2c transactions happening until the driver has been resumed. Signed-off-by: Ben Dooks diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 1fac4e2..b7434d2 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -56,6 +56,7 @@ enum s3c24xx_i2c_state { struct s3c24xx_i2c { spinlock_t lock; wait_queue_head_t wait; + unsigned int suspended:1; struct i2c_msg *msg; unsigned int msg_num; @@ -507,7 +508,7 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int unsigned long timeout; int ret; - if (!(readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN)) + if (i2c->suspended) return -EIO; ret = s3c24xx_i2c_set_master(i2c); @@ -986,17 +987,26 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev) } #ifdef CONFIG_PM +static int s3c24xx_i2c_suspend_late(struct platform_device *dev, + pm_message_t msg) +{ + struct s3c24xx_i2c *i2c = platform_get_drvdata(dev); + i2c->suspended = 1; + return 0; +} + static int s3c24xx_i2c_resume(struct platform_device *dev) { struct s3c24xx_i2c *i2c = platform_get_drvdata(dev); - if (i2c != NULL) - s3c24xx_i2c_init(i2c); + i2c->suspended = 0; + s3c24xx_i2c_init(i2c); return 0; } #else +#define s3c24xx_i2c_suspend_late NULL #define s3c24xx_i2c_resume NULL #endif @@ -1005,6 +1015,7 @@ static int s3c24xx_i2c_resume(struct platform_device *dev) static struct platform_driver s3c2410_i2c_driver = { .probe = s3c24xx_i2c_probe, .remove = s3c24xx_i2c_remove, + .suspend_late = s3c24xx_i2c_suspend_late, .resume = s3c24xx_i2c_resume, .driver = { .owner = THIS_MODULE, @@ -1015,6 +1026,7 @@ static struct platform_driver s3c2410_i2c_driver = { static struct platform_driver s3c2440_i2c_driver = { .probe = s3c24xx_i2c_probe, .remove = s3c24xx_i2c_remove, + .suspend_late = s3c24xx_i2c_suspend_late, .resume = s3c24xx_i2c_resume, .driver = { .owner = THIS_MODULE, -- cgit v0.10.2