[PATCH v1 2/6] i2c: npcm: Fix timeout calculation

From: Tyrone Ting
Date: Mon Feb 07 2022 - 01:41:04 EST


From: Tali Perry <tali.perry1@xxxxxxxxx>

Use adap.timeout for timeout calculation instead of hard-coded
value of 35ms.
Use syscon to access gcr, instead of "compatible".

Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: Tali Perry <tali.perry1@xxxxxxxxx>
Signed-off-by: Tyrone Ting <kfting@xxxxxxxxxxx>
---
drivers/i2c/busses/i2c-npcm7xx.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 2ad166355ec9..ddeee6f53621 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2047,7 +2047,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
u16 nwrite, nread;
u8 *write_data, *read_data;
u8 slave_addr;
- int timeout;
+ unsigned long timeout;
int ret = 0;
bool read_block = false;
bool read_PEC = false;
@@ -2099,13 +2099,13 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
* 9: bits per transaction (including the ack/nack)
*/
timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite);
- timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
+ timeout = max(bus->adap.timeout, usecs_to_jiffies(timeout_usec));
if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);
return -EINVAL;
}

- time_left = jiffies + msecs_to_jiffies(DEFAULT_STALL_COUNT) + 1;
+ time_left = jiffies + timeout + 1;
do {
/*
* we must clear slave address immediately when the bus is not
@@ -2131,7 +2131,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
}

npcm_i2c_init_params(bus);
- bus->dest_addr = slave_addr;
+ bus->dest_addr = slave_addr << 1;
bus->msgs = msgs;
bus->msgs_num = num;
bus->cmd_err = 0;
@@ -2233,9 +2233,9 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
struct i2c_adapter *adap;
struct clk *i2c_clk;
static struct regmap *gcr_regmap;
- static struct regmap *clk_regmap;
int irq;
int ret;
+ struct device_node *np = pdev->dev.of_node;

bus = devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL);
if (!bus)
@@ -2250,15 +2250,11 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
return PTR_ERR(i2c_clk);
bus->apb_clk = clk_get_rate(i2c_clk);

- gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+ gcr_regmap = syscon_regmap_lookup_by_phandle(np, "syscon");
if (IS_ERR(gcr_regmap))
return PTR_ERR(gcr_regmap);
regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);

- clk_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-clk");
- if (IS_ERR(clk_regmap))
- return PTR_ERR(clk_regmap);
-
bus->reg = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(bus->reg))
return PTR_ERR(bus->reg);
@@ -2269,7 +2265,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
adap = &bus->adap;
adap->owner = THIS_MODULE;
adap->retries = 3;
- adap->timeout = HZ;
+ adap->timeout = msecs_to_jiffies(35);
adap->algo = &npcm_i2c_algo;
adap->quirks = &npcm_i2c_quirks;
adap->algo_data = bus;
--
2.17.1