From: Kalle Jokiniemi <ext-kalle.jokiniemi@xxxxxxxxx> I2C_WE registers were not configured, which caused huge delays in I2C operations while cpu idle was enabled and omap entered WFI. This patch enables all I2C wakeup sources. Signed-off-by: Kalle Jokiniemi <ext-kalle.jokiniemi@xxxxxxxxx> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- drivers/i2c/busses/i2c-omap.c | 27 +++++++++++++++++++++++++++ 1 files changed, 27 insertions(+), 0 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index b202354..96f3bed 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -52,6 +52,8 @@ #define OMAP_I2C_IE_REG 0x04 #define OMAP_I2C_STAT_REG 0x08 #define OMAP_I2C_IV_REG 0x0c +/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */ +#define OMAP_I2C_WE_REG 0x0c #define OMAP_I2C_SYSS_REG 0x10 #define OMAP_I2C_BUF_REG 0x14 #define OMAP_I2C_CNT_REG 0x18 @@ -89,6 +91,24 @@ #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */ #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */ +/* I2C WE wakeup enable register */ +#define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */ +#define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */ +#define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/ +#define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */ +#define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */ +#define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */ +#define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */ +#define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */ +#define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */ +#define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */ + +#define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \ + OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \ + OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \ + OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \ + OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE) + /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */ #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */ #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */ @@ -279,6 +299,13 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) __ffs(SYSC_CLOCKACTIVITY_MASK)); omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, v); + /* + * Enabling all wakup sources to stop I2C freezing on + * WFI instruction. + * REVISIT: Some wkup sources might not be needed. + */ + omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, + OMAP_I2C_WE_ALL); } } -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
