lkml.org 
[lkml]   [2011]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/7 v2] i2c-eg20t: Fix 10bit access issue
Date
Reported-by: Jeffrey (Sheng-Hui) Chu <jeffchu@broadcom.com>
Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
---
V2: Update Jeffrey's comments.
---
drivers/i2c/busses/i2c-eg20t.c | 65 ++++++++++++++++++++++++++++++++++++++-
1 files changed, 63 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
index 5ecbee0..6ee719c 100644
--- a/drivers/i2c/busses/i2c-eg20t.c
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -64,6 +64,7 @@
#define TEN_BIT_ADDR_DEFAULT 0xF000
#define TEN_BIT_ADDR_MASK 0xF0
#define PCH_START 0x0020
+#define PCH_RESTART 0x0004
#define PCH_ESR_START 0x0001
#define PCH_BUFF_START 0x1
#define PCH_REPSTART 0x0004
@@ -411,7 +412,7 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
}

if (msgs->flags & I2C_M_TEN) {
- addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
+ addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06;
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
if (first)
pch_i2c_start(adap);
@@ -483,6 +484,19 @@ static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap)
}

/**
+ * pch_i2c_restart() - Generate I2C restart condition in normal mode.
+ * @adap: Pointer to struct i2c_algo_pch_data.
+ *
+ * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA.
+ */
+static void pch_i2c_restart(struct i2c_algo_pch_data *adap)
+{
+ void __iomem *p = adap->pch_base_address;
+ pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
+ pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART);
+}
+
+/**
* pch_i2c_readbytes() - read data from I2C bus in normal mode.
* @i2c_adap: Pointer to the struct i2c_adapter.
* @msgs: Pointer to i2c_msg structure.
@@ -499,6 +513,7 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
u32 length;
u32 addr;
u32 addr_2_msb;
+ u32 addr_8_lsb;
void __iomem *p = adap->pch_base_address;

length = msgs->len;
@@ -514,9 +529,55 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
}

if (msgs->flags & I2C_M_TEN) {
- addr_2_msb = (((addr & I2C_MSB_2B_MSK) >> 7) | (I2C_RD));
+ addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
+ if (first)
+ pch_i2c_start(adap);

+ rtn = pch_i2c_wait_for_xfer_complete(adap);
+ if (rtn == 0) {
+ if (pch_i2c_getack(adap)) {
+ pch_dbg(adap, "Receive NACK for slave address"
+ "setting\n");
+ return -EIO;
+ }
+ addr_8_lsb = (addr & I2C_ADDR_MSK);
+ iowrite32(addr_8_lsb, p + PCH_I2CDR);
+ } else if (rtn == -EIO) { /* Arbitration Lost */
+ pch_err(adap, "Lost Arbitration\n");
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR,
+ I2CMAL_BIT);
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR,
+ I2CMIF_BIT);
+ pch_i2c_init(adap);
+ return -EAGAIN;
+ } else { /* wait-event timeout */
+ pch_i2c_stop(adap);
+ return -ETIME;
+ }
+ pch_i2c_restart(adap);
+ rtn = pch_i2c_wait_for_xfer_complete(adap);
+ if (rtn == 0) {
+ if (pch_i2c_getack(adap)) {
+ pch_dbg(adap, "Receive NACK for slave address"
+ "setting\n");
+ return -EIO;
+ }
+ addr_2_msb |= I2C_RD;
+ iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK,
+ p + PCH_I2CDR);
+ } else if (rtn == -EIO) { /* Arbitration Lost */
+ pch_err(adap, "Lost Arbitration\n");
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR,
+ I2CMAL_BIT);
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR,
+ I2CMIF_BIT);
+ pch_i2c_init(adap);
+ return -EAGAIN;
+ } else { /* wait-event timeout */
+ pch_i2c_stop(adap);
+ return -ETIME;
+ }
} else {
/* 7 address bits + R/W bit */
addr = (((addr) << 1) | (I2C_RD));
--
1.7.4.4


\
 
 \ /
  Last update: 2011-10-12 06:17    [W:0.071 / U:2.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site