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| author | Shawn Nematbakhsh <shawnn@chromium.org> | 2015-01-20 18:40:05 -0800 |
|---|---|---|
| committer | ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> | 2015-01-21 06:44:41 +0000 |
| commit | 2f6f8b35480857a96ac77162155297cb80c9480d (patch) | |
| tree | 63fa8b9237069cc5f4e606c4204dc1eb816374fb | |
| parent | 194bde63670528c456bcc3b5701d64fd01f8fc1d (diff) | |
| download | chrome-ec-2f6f8b35480857a96ac77162155297cb80c9480d.tar.gz | |
pi3usb9281: Lock access to MUX GPIO while in use
Lock access to the MUX GPIO to prevent other tasks from toggling away
from our active chip while in use.
BUG=chrome-os-partner:35567
TEST=Manual on samus_pd. Boot system, verify that no "write failed"
print is seen. Also verify that charger detection functions as expected.
BRANCH=Samus
Change-Id: Ica02b8fbd8f9ee04f6389ce0b0e5bd58104ff698
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/242125
Reviewed-by: Alec Berg <alecaberg@chromium.org>
| -rw-r--r-- | driver/usb_switch_pi3usb9281.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/driver/usb_switch_pi3usb9281.c b/driver/usb_switch_pi3usb9281.c index fd7eecd4d4..d04ea09b8a 100644 --- a/driver/usb_switch_pi3usb9281.c +++ b/driver/usb_switch_pi3usb9281.c @@ -9,6 +9,7 @@ #include "gpio.h" #include "hooks.h" #include "i2c.h" +#include "task.h" #include "timer.h" #include "pi3usb9281.h" #include "util.h" @@ -25,13 +26,22 @@ #ifdef CONFIG_USB_SWITCH_PI3USB9281_MUX_GPIO #define PI3USB9281_COUNT 2 +struct mutex mux_lock; static inline void select_chip(uint8_t chip_idx) { + mutex_lock(&mux_lock); gpio_set_level(CONFIG_USB_SWITCH_PI3USB9281_MUX_GPIO, chip_idx); } + +static inline void unselect_chip(void) +{ + /* Just release the mutex, no need to change the mux gpio */ + mutex_unlock(&mux_lock); +} #else #define PI3USB9281_COUNT 1 #define select_chip(x) +#define unselect_chip() #endif static int saved_interrupts[PI3USB9281_COUNT]; @@ -42,6 +52,8 @@ uint8_t pi3usb9281_read(uint8_t chip_idx, uint8_t reg) select_chip(chip_idx); res = i2c_read8(I2C_PORT_MASTER, PI3USB9281_I2C_ADDR, reg, &val); + unselect_chip(); + if (res) return 0xee; @@ -54,6 +66,8 @@ int pi3usb9281_write(uint8_t chip_idx, uint8_t reg, uint8_t val) select_chip(chip_idx); res = i2c_write8(I2C_PORT_MASTER, PI3USB9281_I2C_ADDR, reg, val); + unselect_chip(); + if (res) CPRINTS("PI3USB9281 I2C write failed"); return res; |