i2c-omap: Enable I2C wakeups for 34xx
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@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
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 @@
__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);
}
}