From: "Jett.Zhou" <[email protected]> Add qos as constraint for cpu-idle, which is standard way, then sysfs could get accurae result.
Change-Id: I4165e01ca2c30f8422b4b4850497c70233d741f8 Signed-off-by: Jett.Zhou <[email protected]> diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index 5893110..f3811d5 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -38,6 +38,7 @@ #include <linux/slab.h> #include <linux/io.h> #include <linux/i2c/pxa-i2c.h> +#include <plat/pm.h> #include <asm/irq.h> @@ -173,6 +174,7 @@ struct pxa_i2c { unsigned int fast_mode :1; unsigned int ilcr; unsigned int iwcr; + struct pm_qos_request qos_idle; }; #define _IBMR(i2c) ((i2c)->reg_ibmr) @@ -729,7 +731,7 @@ static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c) static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num) { - unsigned long timeout = 500000; /* 5 seconds */ + unsigned long timeout = 100000; /* 1 seconds */ int ret = 0; ret = i2c_pxa_pio_set_master(i2c); @@ -742,6 +744,8 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, i2c->msg_ptr = 0; i2c->irqlogidx = 0; + pm_qos_update_request(&i2c->qos_idle, PM_QOS_CONSTRAINT); + i2c_pxa_start_message(i2c); while (i2c->msg_num > 0 && --timeout) { @@ -751,6 +755,7 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, i2c_pxa_stop_message(i2c); + pm_qos_update_request(&i2c->qos_idle, PM_QOS_DEFAULT_VALUE); /* * We place the return code in i2c->msg_idx. */ @@ -760,6 +765,9 @@ out: if (timeout == 0) i2c_pxa_scream_blue_murder(i2c, "timeout"); + if (ret < 0) + i2c_pxa_reset(i2c); + return ret; } @@ -797,6 +805,8 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num) i2c->msg_ptr = 0; i2c->irqlogidx = 0; + pm_qos_update_request(&i2c->qos_idle, PM_QOS_CONSTRAINT); + i2c_pxa_start_message(i2c); spin_unlock_irq(&i2c->lock); @@ -804,9 +814,11 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num) /* * The rest of the processing occurs in the interrupt handler. */ - timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); + timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 1); i2c_pxa_stop_message(i2c); + pm_qos_update_request(&i2c->qos_idle, PM_QOS_DEFAULT_VALUE); + /* * We place the return code in i2c->msg_idx. */ @@ -1146,6 +1158,8 @@ static int i2c_pxa_probe(struct platform_device *dev) struct resource *res = NULL; int ret, irq; + int pm_qos_class = PM_QOS_CPUIDLE_KEEP_DDR; + i2c = kzalloc(sizeof(struct pxa_i2c), GFP_KERNEL); if (!i2c) { ret = -ENOMEM; @@ -1171,7 +1185,10 @@ static int i2c_pxa_probe(struct platform_device *dev) } i2c->adap.owner = THIS_MODULE; - i2c->adap.retries = 5; + i2c->adap.retries = 3; + + pm_qos_add_request(&i2c->qos_idle, pm_qos_class, + PM_QOS_DEFAULT_VALUE); spin_lock_init(&i2c->lock); init_waitqueue_head(&i2c->wait); @@ -1274,6 +1291,7 @@ eclk: kfree(i2c); emalloc: release_mem_region(res->start, resource_size(res)); + pm_qos_remove_request(&i2c->qos_idle); return ret; } @@ -1282,6 +1300,7 @@ static int __exit i2c_pxa_remove(struct platform_device *dev) struct pxa_i2c *i2c = platform_get_drvdata(dev); platform_set_drvdata(dev, NULL); + pm_qos_remove_request(&i2c->qos_idle); i2c_del_adapter(&i2c->adap); if (!i2c->use_pio) -- 1.7.5.4 -- 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
