From dcc4ec26942d3bae2c5a82ab8346ab53b540a171 Mon Sep 17 00:00:00 2001 From: Nishanth Menon Date: Thu, 20 Aug 2009 11:21:14 -0500 Subject: i2c-omap: Fix I2C status ACK I2C status ack for [RX]RDR and [RX]RDY could cause race conditions of clearing the event twice and a violation of the programing sequence as defined in TRM This patch fixes the same. Signed-off-by: Nishanth Menon Signed-off-by: Moiz Sonasath Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-omap.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'drivers/i2c/busses/i2c-omap.c') diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index d258b02aef4..94639d0aabd 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -674,7 +674,14 @@ omap_i2c_isr(int this_irq, void *dev_id) err = 0; complete: - omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat); + /* + * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be + * acked after the data operation is complete. + * Ref: TRM SWPU114Q Figure 18-31 + */ + omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat & + ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR | + OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); if (stat & OMAP_I2C_STAT_NACK) { err |= OMAP_I2C_STAT_NACK; -- cgit v1.2.3-70-g09d2 From dd11976aea15bde53ce40b076dd5fa462c74f41a Mon Sep 17 00:00:00 2001 From: Moiz Sonasath Date: Thu, 20 Aug 2009 11:21:15 -0500 Subject: i2c-omap: ACK pending [R/X]DR and [R/X]RDY interrupts ACK any pending read/write interrupts before exiting the ISR either after completing the operation [ARDY interrupt] or in case of an error [NACK|AL interrupt] Signed-off-by: Moiz Sonasath Signed-off-by: Vikram Pandita Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-omap.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/i2c/busses/i2c-omap.c') diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 94639d0aabd..16b39f470a7 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -694,6 +694,9 @@ complete: } if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { + omap_i2c_ack_stat(dev, stat & + (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR | + OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); omap_i2c_complete_cmd(dev, err); return IRQ_HANDLED; } -- cgit v1.2.3-70-g09d2 From 61149787d65b4a2f9c638d363dc65e13cb063e29 Mon Sep 17 00:00:00 2001 From: Moiz Sonasath Date: Thu, 20 Aug 2009 11:21:16 -0500 Subject: i2c-omap: Enable workaround for Errata 1.153 based on Silicon Errata 1.153 has been fixed on OMAP 3630|4430 with the use of a later version of I2C IP block. The errata impacts OMAP 2420|2430|3430, enable the workaround for these based on I2C IP block revision number instead of OMAP CPU type Signed-off-by: Moiz Sonasath Signed-off-by: Vikram Pandita Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-omap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/i2c/busses/i2c-omap.c') diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 16b39f470a7..827da085813 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -784,7 +784,7 @@ complete: * memory to the I2C interface. */ - if (cpu_is_omap34xx()) { + if (dev->rev <= OMAP_I2C_REV_ON_3430) { while (!(stat & OMAP_I2C_STAT_XUDF)) { if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); -- cgit v1.2.3-70-g09d2