diff options
| author | Vic Yang <victoryang@chromium.org> | 2014-08-25 15:12:34 -0700 |
|---|---|---|
| committer | chrome-internal-fetch <chrome-internal-fetch@google.com> | 2014-08-26 21:02:49 +0000 |
| commit | b22c10ce2e5d8186cff4623dbf6fb18ee6a62017 (patch) | |
| tree | 3f2ef8edc81892b38e098be471f8355482d5786b | |
| parent | 687f9032d1a30455da1b86b8878e91127539be46 (diff) | |
| download | chrome-ec-b22c10ce2e5d8186cff4623dbf6fb18ee6a62017.tar.gz | |
ryu: gate SCL to PI3USB9281
As a short term workaround for the I2C problem of PI3USB9281, we're
gating its SCL input when it's not addressed. This workaround will be
removed once we have the silicon fix.
BUG=chrome-os-partner:31526
TEST=Sanity check on P0 boards.
BRANCH=None
Change-Id: I57daf25f2ad2d94ac7e4192050b4d6bbdae9d51d
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/214064
Reviewed-by: Randall Spangler <rspangler@chromium.org>
| -rw-r--r-- | board/ryu/board.h | 8 | ||||
| -rw-r--r-- | board/ryu/gpio.inc | 3 | ||||
| -rw-r--r-- | chip/stm32/i2c-stm32f0.c | 12 | ||||
| -rw-r--r-- | include/config.h | 11 |
4 files changed, 34 insertions, 0 deletions
diff --git a/board/ryu/board.h b/board/ryu/board.h index ffeda6f743..768f71fb1e 100644 --- a/board/ryu/board.h +++ b/board/ryu/board.h @@ -35,6 +35,14 @@ #undef CONFIG_CONSOLE_CMDHELP #define CONFIG_INDUCTIVE_CHARGING +/* + * Pericom I2C workaround + * TODO(crosbug.com/p/31529): Remove this. + */ +#define CONFIG_I2C_SCL_GATE_PORT I2C_PORT_MASTER +#define CONFIG_I2C_SCL_GATE_ADDR 0x4a +#define CONFIG_I2C_SCL_GATE_GPIO GPIO_PERICOM_CLK_EN + /* Charging/Power configuration */ #undef CONFIG_BATTERY_RYU /* TODO implement */ #define CONFIG_BATTERY_BQ27541 diff --git a/board/ryu/gpio.inc b/board/ryu/gpio.inc index b7579ebdb3..979722b450 100644 --- a/board/ryu/gpio.inc +++ b/board/ryu/gpio.inc @@ -90,6 +90,9 @@ GPIO(MASTER_I2C_SDA, B, 9, GPIO_INPUT, NULL) GPIO(SLAVE_I2C_SCL, B, 10, GPIO_INPUT, NULL) GPIO(SLAVE_I2C_SDA, B, 11, GPIO_INPUT, NULL) +/* SCL gating for PI3USB9281 */ +GPIO(PERICOM_CLK_EN, C, 15, GPIO_OUT_LOW, NULL) + /* Case closed debugging. */ GPIO(PD_DISABLE_DEBUG, C, 5, GPIO_OUT_HIGH, NULL) GPIO(SPI_FLASH_NSS, B, 12, GPIO_INPUT, NULL) diff --git a/chip/stm32/i2c-stm32f0.c b/chip/stm32/i2c-stm32f0.c index c6cfa9e156..8db1d97f2d 100644 --- a/chip/stm32/i2c-stm32f0.c +++ b/chip/stm32/i2c-stm32f0.c @@ -291,6 +291,12 @@ int i2c_xfer(int port, int slave_addr, const uint8_t *out, int out_bytes, int rv = EC_SUCCESS; int i; +#if defined(CONFIG_I2C_SCL_GATE_ADDR) && defined(CONFIG_I2C_SCL_GATE_PORT) + if (port == CONFIG_I2C_SCL_GATE_PORT && + slave_addr == CONFIG_I2C_SCL_GATE_ADDR) + gpio_set_level(CONFIG_I2C_SCL_GATE_GPIO, 1); +#endif + ASSERT(out || !out_bytes); ASSERT(in || !in_bytes); @@ -367,6 +373,12 @@ xfer_exit: STM32_I2C_CR1(port) |= STM32_I2C_CR1_PE; } +#ifdef CONFIG_I2C_SCL_GATE_ADDR + if (port == CONFIG_I2C_SCL_GATE_PORT && + slave_addr == CONFIG_I2C_SCL_GATE_ADDR) + gpio_set_level(CONFIG_I2C_SCL_GATE_GPIO, 0); +#endif + return rv; } diff --git a/include/config.h b/include/config.h index 8337c8ca03..1221a6f6bc 100644 --- a/include/config.h +++ b/include/config.h @@ -569,6 +569,17 @@ #undef CONFIG_I2C_PASSTHROUGH #undef CONFIG_I2C_PASSTHRU_RESTRICTED +/* + * I2C SCL gating. + * + * If CONFIG_I2C_SCL_GATE_ADDR/PORT is defined, whenever the defined address + * is addressed, CONFIG_I2C_SCL_GATE_GPIO is set to high. When the I2C + * transaction is done, the pin is set back to low. + */ +#undef CONFIG_I2C_SCL_GATE_PORT +#undef CONFIG_I2C_SCL_GATE_ADDR +#undef CONFIG_I2C_SCL_GATE_GPIO + /*****************************************************************************/ /* Inductive charging */ |