* [PATCH V5 2/7] i2c: tegra: remove unnecessary variable init
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-12 10:21 ` Wolfram Sang
2019-06-11 10:51 ` [PATCH V5 3/7] i2c: tegra: fix alignment and spacing violations Bitan Biswas
` (5 subsequent siblings)
6 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Remove variable initializations in functions that
are followed by assignments before use
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/i2c/busses/i2c-tegra.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 00692d8..f7116b7 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -689,7 +689,7 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit)
u32 val;
int err;
u32 clk_divisor, clk_multiplier;
- u32 tsu_thd = 0;
+ u32 tsu_thd;
u8 tlow, thigh;
err = pm_runtime_get_sync(i2c_dev->dev);
@@ -1218,7 +1218,7 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
{
struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
int i;
- int ret = 0;
+ int ret;
ret = pm_runtime_get_sync(i2c_dev->dev);
if (ret < 0) {
@@ -1489,7 +1489,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
void __iomem *base;
phys_addr_t base_phys;
int irq;
- int ret = 0;
+ int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base_phys = res->start;
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 2/7] i2c: tegra: remove unnecessary variable init
2019-06-11 10:51 ` [PATCH V5 2/7] i2c: tegra: remove unnecessary variable init Bitan Biswas
@ 2019-06-12 10:21 ` Wolfram Sang
0 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:21 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 299 bytes --]
On Tue, Jun 11, 2019 at 03:51:09AM -0700, Bitan Biswas wrote:
> Remove variable initializations in functions that
> are followed by assignments before use
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Applied to for-next, thanks!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH V5 3/7] i2c: tegra: fix alignment and spacing violations
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
2019-06-11 10:51 ` [PATCH V5 2/7] i2c: tegra: remove unnecessary variable init Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-12 10:21 ` Wolfram Sang
2019-06-11 10:51 ` [PATCH V5 4/7] i2c: tegra: add spinlock definition comment Bitan Biswas
` (4 subsequent siblings)
6 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Fix checkpatch.pl alignment and blank line check(s) in i2c-tegra.c
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/i2c/busses/i2c-tegra.c | 35 +++++++++++++++++++----------------
1 file changed, 19 insertions(+), 16 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index f7116b7..2d381de 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -295,7 +295,7 @@ static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
* to the I2C block inside the DVC block
*/
static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
- unsigned long reg)
+ unsigned long reg)
{
if (i2c_dev->is_dvc)
reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40;
@@ -303,7 +303,7 @@ static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
}
static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
- unsigned long reg)
+ unsigned long reg)
{
writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
@@ -318,13 +318,13 @@ static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
}
static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
- unsigned long reg, int len)
+ unsigned long reg, int len)
{
writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
}
static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data,
- unsigned long reg, int len)
+ unsigned long reg, int len)
{
readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
}
@@ -669,10 +669,11 @@ static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev)
i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);
if (in_interrupt())
err = readl_poll_timeout_atomic(addr, val, val == 0,
- 1000, I2C_CONFIG_LOAD_TIMEOUT);
+ 1000,
+ I2C_CONFIG_LOAD_TIMEOUT);
else
- err = readl_poll_timeout(addr, val, val == 0,
- 1000, I2C_CONFIG_LOAD_TIMEOUT);
+ err = readl_poll_timeout(addr, val, val == 0, 1000,
+ I2C_CONFIG_LOAD_TIMEOUT);
if (err) {
dev_warn(i2c_dev->dev,
@@ -1013,7 +1014,8 @@ static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap)
}
static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
- struct i2c_msg *msg, enum msg_end_type end_state)
+ struct i2c_msg *msg,
+ enum msg_end_type end_state)
{
u32 packet_header;
u32 int_mask;
@@ -1150,9 +1152,8 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
if (err)
return err;
- time_left = wait_for_completion_timeout(
- &i2c_dev->dma_complete,
- msecs_to_jiffies(xfer_time));
+ time_left = wait_for_completion_timeout(&i2c_dev->dma_complete,
+ msecs_to_jiffies(xfer_time));
if (time_left == 0) {
dev_err(i2c_dev->dev, "DMA transfer timeout\n");
dmaengine_terminate_sync(i2c_dev->msg_read ?
@@ -1214,7 +1215,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
}
static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
- int num)
+ int num)
{
struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
int i;
@@ -1260,14 +1261,15 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
{
struct device_node *np = i2c_dev->dev->of_node;
int ret;
+ bool multi_mode;
ret = of_property_read_u32(np, "clock-frequency",
- &i2c_dev->bus_clk_rate);
+ &i2c_dev->bus_clk_rate);
if (ret)
i2c_dev->bus_clk_rate = 100000; /* default clock rate */
- i2c_dev->is_multimaster_mode = of_property_read_bool(np,
- "multi-master");
+ multi_mode = of_property_read_bool(np, "multi-master");
+ i2c_dev->is_multimaster_mode = multi_mode;
}
static const struct i2c_algorithm tegra_i2c_algo = {
@@ -1611,7 +1613,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
}
ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
- tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
+ tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
if (ret) {
dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
goto release_dma;
@@ -1704,6 +1706,7 @@ static const struct dev_pm_ops tegra_i2c_pm = {
SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume,
NULL)
};
+
#define TEGRA_I2C_PM (&tegra_i2c_pm)
#else
#define TEGRA_I2C_PM NULL
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 3/7] i2c: tegra: fix alignment and spacing violations
2019-06-11 10:51 ` [PATCH V5 3/7] i2c: tegra: fix alignment and spacing violations Bitan Biswas
@ 2019-06-12 10:21 ` Wolfram Sang
0 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:21 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 274 bytes --]
On Tue, Jun 11, 2019 at 03:51:10AM -0700, Bitan Biswas wrote:
> Fix checkpatch.pl alignment and blank line check(s) in i2c-tegra.c
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Applied to for-next, thanks!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH V5 4/7] i2c: tegra: add spinlock definition comment
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
2019-06-11 10:51 ` [PATCH V5 2/7] i2c: tegra: remove unnecessary variable init Bitan Biswas
2019-06-11 10:51 ` [PATCH V5 3/7] i2c: tegra: fix alignment and spacing violations Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-12 10:21 ` Wolfram Sang
2019-06-11 10:51 ` [PATCH V5 5/7] i2c: tegra: fix msleep warning Bitan Biswas
` (3 subsequent siblings)
6 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Fix checkpatch.pl CHECK as follows:
CHECK: spinlock_t definition without comment
+ spinlock_t xfer_lock;
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/i2c/busses/i2c-tegra.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 2d381de..bececa6 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -269,6 +269,7 @@ struct tegra_i2c_dev {
u32 bus_clk_rate;
u16 clk_divisor_non_hs_mode;
bool is_multimaster_mode;
+ /* xfer_lock: lock to serialize transfer submission and processing */
spinlock_t xfer_lock;
struct dma_chan *tx_dma_chan;
struct dma_chan *rx_dma_chan;
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 4/7] i2c: tegra: add spinlock definition comment
2019-06-11 10:51 ` [PATCH V5 4/7] i2c: tegra: add spinlock definition comment Bitan Biswas
@ 2019-06-12 10:21 ` Wolfram Sang
0 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:21 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 324 bytes --]
On Tue, Jun 11, 2019 at 03:51:11AM -0700, Bitan Biswas wrote:
> Fix checkpatch.pl CHECK as follows:
> CHECK: spinlock_t definition without comment
> + spinlock_t xfer_lock;
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Applied to for-next, thanks!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH V5 5/7] i2c: tegra: fix msleep warning
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
` (2 preceding siblings ...)
2019-06-11 10:51 ` [PATCH V5 4/7] i2c: tegra: add spinlock definition comment Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-12 10:21 ` Wolfram Sang
2019-06-11 10:51 ` [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check Bitan Biswas
` (2 subsequent siblings)
6 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Fix checkpatch.pl WARNING for delay of approximately 1msec
in flush i2c FIFO polling loop by using usleep_range(1000, 2000):
WARNING: msleep < 20ms can sleep for up to 20ms; see ...
Documentation/timers/timers-howto.txt
+ msleep(1);
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/i2c/busses/i2c-tegra.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index bececa6..4dfb4c1 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -476,7 +476,7 @@ static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev)
dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n");
return -ETIMEDOUT;
}
- msleep(1);
+ usleep_range(1000, 2000);
}
return 0;
}
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 5/7] i2c: tegra: fix msleep warning
2019-06-11 10:51 ` [PATCH V5 5/7] i2c: tegra: fix msleep warning Bitan Biswas
@ 2019-06-12 10:21 ` Wolfram Sang
0 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:21 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 466 bytes --]
On Tue, Jun 11, 2019 at 03:51:12AM -0700, Bitan Biswas wrote:
> Fix checkpatch.pl WARNING for delay of approximately 1msec
> in flush i2c FIFO polling loop by using usleep_range(1000, 2000):
> WARNING: msleep < 20ms can sleep for up to 20ms; see ...
> Documentation/timers/timers-howto.txt
> + msleep(1);
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Applied to for-next, thanks!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
` (3 preceding siblings ...)
2019-06-11 10:51 ` [PATCH V5 5/7] i2c: tegra: fix msleep warning Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-12 10:24 ` Wolfram Sang
` (2 more replies)
2019-06-11 10:51 ` [PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON Bitan Biswas
2019-06-12 10:21 ` [PATCH V5 1/7] i2c: tegra: clean up macros Wolfram Sang
6 siblings, 3 replies; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Fix expression for residual bytes(less than word) transfer
in I2C PIO mode RX/TX.
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
---
drivers/i2c/busses/i2c-tegra.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 4dfb4c1..0596c12 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -514,7 +514,8 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
* If there is a partial word at the end of buf, handle it manually to
* prevent overwriting past the end of buf
*/
- if (rx_fifo_avail > 0 && buf_remaining > 0) {
+ if (rx_fifo_avail > 0 &&
+ (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
BUG_ON(buf_remaining > 3);
val = i2c_readl(i2c_dev, I2C_RX_FIFO);
val = cpu_to_le32(val);
@@ -557,11 +558,10 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
words_to_transfer = tx_fifo_avail;
/*
- * Update state before writing to FIFO. If this casues us
+ * Update state before writing to FIFO. If this causes us
* to finish writing all bytes (AKA buf_remaining goes to 0) we
* have a potential for an interrupt (PACKET_XFER_COMPLETE is
- * not maskable). We need to make sure that the isr sees
- * buf_remaining as 0 and doesn't call us back re-entrantly.
+ * not maskable).
*/
buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
tx_fifo_avail -= words_to_transfer;
@@ -580,7 +580,8 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
* prevent reading past the end of buf, which could cross a page
* boundary and fault.
*/
- if (tx_fifo_avail > 0 && buf_remaining > 0) {
+ if (tx_fifo_avail > 0 &&
+ (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
BUG_ON(buf_remaining > 3);
memcpy(&val, buf, buf_remaining);
val = le32_to_cpu(val);
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-11 10:51 ` [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check Bitan Biswas
@ 2019-06-12 10:24 ` Wolfram Sang
2019-06-13 11:43 ` Bitan Biswas
2019-06-13 11:52 ` Laxman Dewangan
2019-06-12 13:55 ` Dmitry Osipenko
2019-06-12 14:30 ` Dmitry Osipenko
2 siblings, 2 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:24 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 586 bytes --]
On Tue, Jun 11, 2019 at 03:51:13AM -0700, Bitan Biswas wrote:
> Fix expression for residual bytes(less than word) transfer
> in I2C PIO mode RX/TX.
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
I applied patches 1-5 to my for-next tree now. No need to resend them
anymore, you can focus on the remaining patches now.
Question: The nominal maintainer for this driver is
Laxman Dewangan <ldewangan@nvidia.com> (supporter:TEGRA I2C DRIVER)
I wonder if he is still around and interested?
That aside, thanks a lot Dmitry for the review of this series!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-12 10:24 ` Wolfram Sang
@ 2019-06-13 11:43 ` Bitan Biswas
2019-06-13 11:52 ` Laxman Dewangan
1 sibling, 0 replies; 25+ messages in thread
From: Bitan Biswas @ 2019-06-13 11:43 UTC (permalink / raw)
To: Wolfram Sang
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
On 6/12/19 3:24 AM, Wolfram Sang wrote:
> On Tue, Jun 11, 2019 at 03:51:13AM -0700, Bitan Biswas wrote:
>> Fix expression for residual bytes(less than word) transfer
>> in I2C PIO mode RX/TX.
>>
>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>
> I applied patches 1-5 to my for-next tree now. No need to resend them
> anymore, you can focus on the remaining patches now.
>
> Question: The nominal maintainer for this driver is
>
> Laxman Dewangan <ldewangan@nvidia.com> (supporter:TEGRA I2C DRIVER)
>
> I wonder if he is still around and interested?
>
> That aside, thanks a lot Dmitry for the review of this series!
>
Thanks Wolfram. I shall work on remaining patches.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-12 10:24 ` Wolfram Sang
2019-06-13 11:43 ` Bitan Biswas
@ 2019-06-13 11:52 ` Laxman Dewangan
2019-06-13 13:13 ` Wolfram Sang
1 sibling, 1 reply; 25+ messages in thread
From: Laxman Dewangan @ 2019-06-13 11:52 UTC (permalink / raw)
To: Wolfram Sang, Bitan Biswas
Cc: Thierry Reding, Jonathan Hunter, linux-i2c, linux-tegra,
linux-kernel, Peter Rosin, Dmitry Osipenko, Shardar Mohammed,
Sowjanya Komatineni, Mantravadi Karthik
On Wednesday 12 June 2019 03:54 PM, Wolfram Sang wrote:
> On Tue, Jun 11, 2019 at 03:51:13AM -0700, Bitan Biswas wrote:
>> Fix expression for residual bytes(less than word) transfer
>> in I2C PIO mode RX/TX.
>>
>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> I applied patches 1-5 to my for-next tree now. No need to resend them
> anymore, you can focus on the remaining patches now.
>
> Question: The nominal maintainer for this driver is
>
> Laxman Dewangan <ldewangan@nvidia.com> (supporter:TEGRA I2C DRIVER)
>
> I wonder if he is still around and interested?
>
> That aside, thanks a lot Dmitry for the review of this series!
>
Most of patches are coming from the downstream as part of upstream
effort. Hence not reviewing explicitly.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-13 11:52 ` Laxman Dewangan
@ 2019-06-13 13:13 ` Wolfram Sang
0 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-13 13:13 UTC (permalink / raw)
To: Laxman Dewangan
Cc: Bitan Biswas, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 334 bytes --]
> Most of patches are coming from the downstream as part of upstream effort.
> Hence not reviewing explicitly.
It would help me a lot if you could ack the patches, then, once you are
fine with them. I am really relying on driver maintainers these days. An
ack or rev from them is kinda required and speeds up things
significantly.
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-11 10:51 ` [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check Bitan Biswas
2019-06-12 10:24 ` Wolfram Sang
@ 2019-06-12 13:55 ` Dmitry Osipenko
2019-06-13 9:59 ` Bitan Biswas
2019-06-12 14:30 ` Dmitry Osipenko
2 siblings, 1 reply; 25+ messages in thread
From: Dmitry Osipenko @ 2019-06-12 13:55 UTC (permalink / raw)
To: Bitan Biswas, Laxman Dewangan, Thierry Reding, Jonathan Hunter,
linux-i2c, linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
11.06.2019 13:51, Bitan Biswas пишет:
> Fix expression for residual bytes(less than word) transfer
> in I2C PIO mode RX/TX.
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> ---
> drivers/i2c/busses/i2c-tegra.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index 4dfb4c1..0596c12 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -514,7 +514,8 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
> * If there is a partial word at the end of buf, handle it manually to
> * prevent overwriting past the end of buf
> */
> - if (rx_fifo_avail > 0 && buf_remaining > 0) {
> + if (rx_fifo_avail > 0 &&
> + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
The buf_remaining >= BYTES_PER_FIFO_WORD is not possible to happen
because there are three possible cases:
1) buf_remaining > rx_fifo_avail * 4:
In this case rx_fifo_avail = 0
2) buf_remaining < rx_fifo_avail * 4;
In this case buf_remaining is always < 4 because
words_to_transfer is a buf_remaining rounded down to 4
and then divided by 4. Hence:
buf_remaining -= (buf_remaining / 4) * 4 always results
into buf_remaining < 4.
3) buf_remaining == rx_fifo_avail * 4:
In this case rx_fifo_avail = 0 and buf_remaining = 0.
Case 2 should never happen and means that something gone wrong.
> BUG_ON(buf_remaining > 3);
> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
> val = cpu_to_le32(val);
> @@ -557,11 +558,10 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
> words_to_transfer = tx_fifo_avail;
>
> /*
> - * Update state before writing to FIFO. If this casues us
> + * Update state before writing to FIFO. If this causes us
> * to finish writing all bytes (AKA buf_remaining goes to 0) we
> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
> - * not maskable). We need to make sure that the isr sees
> - * buf_remaining as 0 and doesn't call us back re-entrantly.
> + * not maskable).
> */
> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
> tx_fifo_avail -= words_to_transfer;
> @@ -580,7 +580,8 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
> * prevent reading past the end of buf, which could cross a page
> * boundary and fault.
> */
> - if (tx_fifo_avail > 0 && buf_remaining > 0) {
> + if (tx_fifo_avail > 0 &&
> + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
> BUG_ON(buf_remaining > 3);
> memcpy(&val, buf, buf_remaining);
> val = le32_to_cpu(val);
>
Same as for RX.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-12 13:55 ` Dmitry Osipenko
@ 2019-06-13 9:59 ` Bitan Biswas
0 siblings, 0 replies; 25+ messages in thread
From: Bitan Biswas @ 2019-06-13 9:59 UTC (permalink / raw)
To: Dmitry Osipenko, Laxman Dewangan, Thierry Reding,
Jonathan Hunter, linux-i2c, linux-tegra, linux-kernel,
Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
On 6/12/19 6:55 AM, Dmitry Osipenko wrote:
> 11.06.2019 13:51, Bitan Biswas пишет:
>> Fix expression for residual bytes(less than word) transfer
>> in I2C PIO mode RX/TX.
>>
>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>> ---
>> drivers/i2c/busses/i2c-tegra.c | 11 ++++++-----
>> 1 file changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
>> index 4dfb4c1..0596c12 100644
>> --- a/drivers/i2c/busses/i2c-tegra.c
>> +++ b/drivers/i2c/busses/i2c-tegra.c
>> @@ -514,7 +514,8 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>> * If there is a partial word at the end of buf, handle it manually to
>> * prevent overwriting past the end of buf
>> */
>> - if (rx_fifo_avail > 0 && buf_remaining > 0) {
>> + if (rx_fifo_avail > 0 &&
>> + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
>
> The buf_remaining >= BYTES_PER_FIFO_WORD is not possible to happen
> because there are three possible cases:
>
> 1) buf_remaining > rx_fifo_avail * 4:
>
> In this case rx_fifo_avail = 0
>
> 2) buf_remaining < rx_fifo_avail * 4;
>
> In this case buf_remaining is always < 4 because
> words_to_transfer is a buf_remaining rounded down to 4
> and then divided by 4. Hence:
>
> buf_remaining -= (buf_remaining / 4) * 4 always results
> into buf_remaining < 4.
>
> 3) buf_remaining == rx_fifo_avail * 4:
>
> In this case rx_fifo_avail = 0 and buf_remaining = 0.
>
> Case 2 should never happen and means that something gone wrong.
>
Yes I now agree with you. The first condition "rx_fifo_avail > 0"
failure will take care and prevent need for additional checks.
>> BUG_ON(buf_remaining > 3);
>> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
>> val = cpu_to_le32(val);
>> @@ -557,11 +558,10 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
>> words_to_transfer = tx_fifo_avail;
>>
>> /*
>> - * Update state before writing to FIFO. If this casues us
>> + * Update state before writing to FIFO. If this causes us
>> * to finish writing all bytes (AKA buf_remaining goes to 0) we
>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>> - * not maskable). We need to make sure that the isr sees
>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>> + * not maskable).
>> */
>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>> tx_fifo_avail -= words_to_transfer;
>> @@ -580,7 +580,8 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
>> * prevent reading past the end of buf, which could cross a page
>> * boundary and fault.
>> */
>> - if (tx_fifo_avail > 0 && buf_remaining > 0) {
>> + if (tx_fifo_avail > 0 &&
>> + (buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
>> BUG_ON(buf_remaining > 3);
>> memcpy(&val, buf, buf_remaining);
>> val = le32_to_cpu(val);
>>
>
> Same as for RX.
>
Yes shall discard this patch from the next update.
-Thanks,
Bitan
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-11 10:51 ` [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check Bitan Biswas
2019-06-12 10:24 ` Wolfram Sang
2019-06-12 13:55 ` Dmitry Osipenko
@ 2019-06-12 14:30 ` Dmitry Osipenko
2019-06-13 11:30 ` Bitan Biswas
2 siblings, 1 reply; 25+ messages in thread
From: Dmitry Osipenko @ 2019-06-12 14:30 UTC (permalink / raw)
To: Bitan Biswas, Laxman Dewangan, Thierry Reding, Jonathan Hunter,
linux-i2c, linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
11.06.2019 13:51, Bitan Biswas пишет:
> Fix expression for residual bytes(less than word) transfer
> in I2C PIO mode RX/TX.
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> ---
[snip]
> /*
> - * Update state before writing to FIFO. If this casues us
> + * Update state before writing to FIFO. If this causes us
> * to finish writing all bytes (AKA buf_remaining goes to 0) we
> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
> - * not maskable). We need to make sure that the isr sees
> - * buf_remaining as 0 and doesn't call us back re-entrantly.
> + * not maskable).
> */
> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
Looks like the comment could be removed altogether because it doesn't
make sense since interrupt handler is under xfer_lock which is kept
locked during of tegra_i2c_xfer_msg().
Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-12 14:30 ` Dmitry Osipenko
@ 2019-06-13 11:30 ` Bitan Biswas
2019-06-13 12:28 ` Dmitry Osipenko
0 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-13 11:30 UTC (permalink / raw)
To: Dmitry Osipenko, Laxman Dewangan, Thierry Reding,
Jonathan Hunter, linux-i2c, linux-tegra, linux-kernel,
Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
On 6/12/19 7:30 AM, Dmitry Osipenko wrote:
> 11.06.2019 13:51, Bitan Biswas пишет:
>> Fix expression for residual bytes(less than word) transfer
>> in I2C PIO mode RX/TX.
>>
>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>> ---
>
> [snip]
>
>> /*
>> - * Update state before writing to FIFO. If this casues us
>> + * Update state before writing to FIFO. If this causes us
>> * to finish writing all bytes (AKA buf_remaining goes to 0) we
>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>> - * not maskable). We need to make sure that the isr sees
>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>> + * not maskable).
>> */
>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>
> Looks like the comment could be removed altogether because it doesn't
> make sense since interrupt handler is under xfer_lock which is kept
> locked during of tegra_i2c_xfer_msg().
I would push a separate patch to remove this comment because of
xfer_lock in ISR now.
>
> Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
> but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
>
I2C_INT_PACKET_XFER_COMPLETE masking support available in Tegra chips
newer than Tegra30 allows one to not see interrupt after Packet transfer
complete. With the xfer_lock in ISR the scenario discussed in comment
can be ignored.
-regards,
Bitan
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-13 11:30 ` Bitan Biswas
@ 2019-06-13 12:28 ` Dmitry Osipenko
2019-06-14 9:50 ` Bitan Biswas
0 siblings, 1 reply; 25+ messages in thread
From: Dmitry Osipenko @ 2019-06-13 12:28 UTC (permalink / raw)
To: Bitan Biswas, Laxman Dewangan, Thierry Reding, Jonathan Hunter,
linux-i2c, linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
13.06.2019 14:30, Bitan Biswas пишет:
>
>
> On 6/12/19 7:30 AM, Dmitry Osipenko wrote:
>> 11.06.2019 13:51, Bitan Biswas пишет:
>>> Fix expression for residual bytes(less than word) transfer
>>> in I2C PIO mode RX/TX.
>>>
>>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>>> ---
>>
>> [snip]
>>
>>> /*
>>> - * Update state before writing to FIFO. If this casues us
>>> + * Update state before writing to FIFO. If this causes us
>>> * to finish writing all bytes (AKA buf_remaining goes to
>>> 0) we
>>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>>> - * not maskable). We need to make sure that the isr sees
>>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>>> + * not maskable).
>>> */
>>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>>
>> Looks like the comment could be removed altogether because it doesn't
>> make sense since interrupt handler is under xfer_lock which is kept
>> locked during of tegra_i2c_xfer_msg().
> I would push a separate patch to remove this comment because of
> xfer_lock in ISR now.
>
>>
>> Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
>> but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
>>
> I2C_INT_PACKET_XFER_COMPLETE masking support available in Tegra chips
> newer than Tegra30 allows one to not see interrupt after Packet transfer
> complete. With the xfer_lock in ISR the scenario discussed in comment
> can be ignored.
Also note that xfer_lock could be removed and replaced with a just
irq_enable/disable() calls in tegra_i2c_xfer_msg() because we only care
about IRQ not firing during of the preparation process.
It also looks like tegra_i2c_[un]nmask_irq isn't really needed and all
IRQ's could be simply unmasked during the driver's probe, in that case
it may worth to add a kind of "in-progress" flag to catch erroneous
interrupts.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-13 12:28 ` Dmitry Osipenko
@ 2019-06-14 9:50 ` Bitan Biswas
2019-06-14 13:02 ` Dmitry Osipenko
0 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-14 9:50 UTC (permalink / raw)
To: Dmitry Osipenko, Laxman Dewangan, Thierry Reding,
Jonathan Hunter, linux-i2c, linux-tegra, linux-kernel,
Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
On 6/13/19 5:28 AM, Dmitry Osipenko wrote:
> 13.06.2019 14:30, Bitan Biswas пишет:
>>
>>
>> On 6/12/19 7:30 AM, Dmitry Osipenko wrote:
>>> 11.06.2019 13:51, Bitan Biswas пишет:
>>>> Fix expression for residual bytes(less than word) transfer
>>>> in I2C PIO mode RX/TX.
>>>>
>>>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>>>> ---
>>>
>>> [snip]
>>>
>>>> /*
>>>> - * Update state before writing to FIFO. If this casues us
>>>> + * Update state before writing to FIFO. If this causes us
>>>> * to finish writing all bytes (AKA buf_remaining goes to
>>>> 0) we
>>>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>>>> - * not maskable). We need to make sure that the isr sees
>>>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>>>> + * not maskable).
>>>> */
>>>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>>>
>>> Looks like the comment could be removed altogether because it doesn't
>>> make sense since interrupt handler is under xfer_lock which is kept
>>> locked during of tegra_i2c_xfer_msg().
>> I would push a separate patch to remove this comment because of
>> xfer_lock in ISR now.
>>
>>>
>>> Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
>>> but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
>>>
>> I2C_INT_PACKET_XFER_COMPLETE masking support available in Tegra chips
>> newer than Tegra30 allows one to not see interrupt after Packet transfer
>> complete. With the xfer_lock in ISR the scenario discussed in comment
>> can be ignored.
>
> Also note that xfer_lock could be removed and replaced with a just
> irq_enable/disable() calls in tegra_i2c_xfer_msg() because we only care
> about IRQ not firing during of the preparation process.
This should need sufficient testing hence let us do it in a different
series.
>
> It also looks like tegra_i2c_[un]nmask_irq isn't really needed and all
> IRQ's could be simply unmasked during the driver's probe, in that case
> it may worth to add a kind of "in-progress" flag to catch erroneous
> interrupts.
>
TX interrupt needs special handling if this change is done. Hence I
think it should be taken up after sufficient testing in a separate patch.
-regards,
Bitan
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-14 9:50 ` Bitan Biswas
@ 2019-06-14 13:02 ` Dmitry Osipenko
2019-06-18 5:21 ` Bitan Biswas
0 siblings, 1 reply; 25+ messages in thread
From: Dmitry Osipenko @ 2019-06-14 13:02 UTC (permalink / raw)
To: Bitan Biswas, Laxman Dewangan, Thierry Reding, Jonathan Hunter,
linux-i2c, linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
14.06.2019 12:50, Bitan Biswas пишет:
>
>
> On 6/13/19 5:28 AM, Dmitry Osipenko wrote:
>> 13.06.2019 14:30, Bitan Biswas пишет:
>>>
>>>
>>> On 6/12/19 7:30 AM, Dmitry Osipenko wrote:
>>>> 11.06.2019 13:51, Bitan Biswas пишет:
>>>>> Fix expression for residual bytes(less than word) transfer
>>>>> in I2C PIO mode RX/TX.
>>>>>
>>>>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>>>>> ---
>>>>
>>>> [snip]
>>>>
>>>>> /*
>>>>> - * Update state before writing to FIFO. If this casues us
>>>>> + * Update state before writing to FIFO. If this causes us
>>>>> * to finish writing all bytes (AKA buf_remaining goes to
>>>>> 0) we
>>>>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>>>>> - * not maskable). We need to make sure that the isr sees
>>>>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>>>>> + * not maskable).
>>>>> */
>>>>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>>>>
>>>> Looks like the comment could be removed altogether because it doesn't
>>>> make sense since interrupt handler is under xfer_lock which is kept
>>>> locked during of tegra_i2c_xfer_msg().
>>> I would push a separate patch to remove this comment because of
>>> xfer_lock in ISR now.
>>>
>>>>
>>>> Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
>>>> but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
>>>>
>>> I2C_INT_PACKET_XFER_COMPLETE masking support available in Tegra chips
>>> newer than Tegra30 allows one to not see interrupt after Packet transfer
>>> complete. With the xfer_lock in ISR the scenario discussed in comment
>>> can be ignored.
>>
>> Also note that xfer_lock could be removed and replaced with a just
>> irq_enable/disable() calls in tegra_i2c_xfer_msg() because we only care
>> about IRQ not firing during of the preparation process.
> This should need sufficient testing hence let us do it in a different series.
I don't think that there is much to test here since obviously it should work.
>>
>> It also looks like tegra_i2c_[un]nmask_irq isn't really needed and all
>> IRQ's could be simply unmasked during the driver's probe, in that case
>> it may worth to add a kind of "in-progress" flag to catch erroneous
>> interrupts.
>>
> TX interrupt needs special handling if this change is done. Hence I think it should be
> taken up after sufficient testing in a separate patch.
This one is indeed a bit more trickier. Probably another alternative could be to keep GIC
interrupt disabled while no transfer is performed, then you'll have to request interrupt
in a disabled state using IRQ_NOAUTOEN flag.
And yes, that all should be a separate changes if you're going to implement them.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check
2019-06-14 13:02 ` Dmitry Osipenko
@ 2019-06-18 5:21 ` Bitan Biswas
0 siblings, 0 replies; 25+ messages in thread
From: Bitan Biswas @ 2019-06-18 5:21 UTC (permalink / raw)
To: Dmitry Osipenko, Laxman Dewangan, Thierry Reding,
Jonathan Hunter, linux-i2c, linux-tegra, linux-kernel,
Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
On 6/14/19 6:02 AM, Dmitry Osipenko wrote:
> 14.06.2019 12:50, Bitan Biswas пишет:
>>
>>
>> On 6/13/19 5:28 AM, Dmitry Osipenko wrote:
>>> 13.06.2019 14:30, Bitan Biswas пишет:
>>>>
>>>>
>>>> On 6/12/19 7:30 AM, Dmitry Osipenko wrote:
>>>>> 11.06.2019 13:51, Bitan Biswas пишет:
>>>>>> Fix expression for residual bytes(less than word) transfer
>>>>>> in I2C PIO mode RX/TX.
>>>>>>
>>>>>> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
>>>>>> ---
>>>>>
>>>>> [snip]
>>>>>
>>>>>> /*
>>>>>> - * Update state before writing to FIFO. If this casues us
>>>>>> + * Update state before writing to FIFO. If this causes us
>>>>>> * to finish writing all bytes (AKA buf_remaining goes to
>>>>>> 0) we
>>>>>> * have a potential for an interrupt (PACKET_XFER_COMPLETE is
>>>>>> - * not maskable). We need to make sure that the isr sees
>>>>>> - * buf_remaining as 0 and doesn't call us back re-entrantly.
>>>>>> + * not maskable).
>>>>>> */
>>>>>> buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
>>>>>
>>>>> Looks like the comment could be removed altogether because it doesn't
>>>>> make sense since interrupt handler is under xfer_lock which is kept
>>>>> locked during of tegra_i2c_xfer_msg().
>>>> I would push a separate patch to remove this comment because of
>>>> xfer_lock in ISR now.
>>>>
>>>>>
>>>>> Moreover the comment says that "PACKET_XFER_COMPLETE is not maskable",
>>>>> but then what I2C_INT_PACKET_XFER_COMPLETE masking does?
>>>>>
>>>> I2C_INT_PACKET_XFER_COMPLETE masking support available in Tegra chips
>>>> newer than Tegra30 allows one to not see interrupt after Packet transfer
>>>> complete. With the xfer_lock in ISR the scenario discussed in comment
>>>> can be ignored.
>>>
>>> Also note that xfer_lock could be removed and replaced with a just
>>> irq_enable/disable() calls in tegra_i2c_xfer_msg() because we only care
>>> about IRQ not firing during of the preparation process.
>> This should need sufficient testing hence let us do it in a different series.
>
> I don't think that there is much to test here since obviously it should work.
>
I shall push a patch for this as basic i2c read write test passed.
>>>
>>> It also looks like tegra_i2c_[un]nmask_irq isn't really needed and all
>>> IRQ's could be simply unmasked during the driver's probe, in that case
>>> it may worth to add a kind of "in-progress" flag to catch erroneous
>>> interrupts.
>>>
>> TX interrupt needs special handling if this change is done. Hence I think it should be
>> taken up after sufficient testing in a separate patch.
>
> This one is indeed a bit more trickier. Probably another alternative could be to keep GIC
> interrupt disabled while no transfer is performed, then you'll have to request interrupt
> in a disabled state using IRQ_NOAUTOEN flag.
>
> And yes, that all should be a separate changes if you're going to implement them.
>
OK
-Thanks,
Bitan
^ permalink raw reply [flat|nested] 25+ messages in thread
* [PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
` (4 preceding siblings ...)
2019-06-11 10:51 ` [PATCH V5 6/7] i2c: tegra: fix PIO rx/tx residual transfer check Bitan Biswas
@ 2019-06-11 10:51 ` Bitan Biswas
2019-06-11 11:38 ` Dmitry Osipenko
2019-06-12 10:21 ` [PATCH V5 1/7] i2c: tegra: clean up macros Wolfram Sang
6 siblings, 1 reply; 25+ messages in thread
From: Bitan Biswas @ 2019-06-11 10:51 UTC (permalink / raw)
To: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang,
Dmitry Osipenko
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik, Bitan Biswas
Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
as needed. Remove BUG() and make Rx and Tx case handling
similar. Add WARN_ON_ONCE check for non-zero rx_fifo_avail
in tegra_i2c_empty_rx_fifo() and return new error
I2C_ERR_UNEXPECTED_STATUS.
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
---
drivers/i2c/busses/i2c-tegra.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 0596c12..2c8f051 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -73,6 +73,7 @@
#define I2C_ERR_NO_ACK BIT(0)
#define I2C_ERR_ARBITRATION_LOST BIT(1)
#define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
+#define I2C_ERR_UNEXPECTED_STATUS BIT(3)
#define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
#define PACKET_HEADER0_PACKET_ID_SHIFT 16
@@ -516,15 +517,15 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
*/
if (rx_fifo_avail > 0 &&
(buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
- BUG_ON(buf_remaining > 3);
val = i2c_readl(i2c_dev, I2C_RX_FIFO);
val = cpu_to_le32(val);
memcpy(buf, &val, buf_remaining);
buf_remaining = 0;
rx_fifo_avail--;
}
+ if (WARN_ON_ONCE(rx_fifo_avail))
+ return -EINVAL;
- BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
i2c_dev->msg_buf_remaining = buf_remaining;
i2c_dev->msg_buf = buf;
@@ -582,7 +583,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
*/
if (tx_fifo_avail > 0 &&
(buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
- BUG_ON(buf_remaining > 3);
memcpy(&val, buf, buf_remaining);
val = le32_to_cpu(val);
@@ -848,10 +848,16 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
if (!i2c_dev->is_curr_dma_xfer) {
if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
- if (i2c_dev->msg_buf_remaining)
- tegra_i2c_empty_rx_fifo(i2c_dev);
- else
- BUG();
+ if (i2c_dev->msg_buf_remaining) {
+ if (tegra_i2c_empty_rx_fifo(i2c_dev)) {
+ i2c_dev->msg_err |=
+ I2C_ERR_UNEXPECTED_STATUS;
+ goto err;
+ }
+ } else {
+ tegra_i2c_mask_irq(i2c_dev,
+ I2C_INT_RX_FIFO_DATA_REQ);
+ }
}
if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
@@ -877,7 +883,10 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
if (status & I2C_INT_PACKET_XFER_COMPLETE) {
if (i2c_dev->is_curr_dma_xfer)
i2c_dev->msg_buf_remaining = 0;
- BUG_ON(i2c_dev->msg_buf_remaining);
+ if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) {
+ i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
+ goto err;
+ }
complete(&i2c_dev->msg_complete);
}
goto done;
--
2.7.4
^ permalink raw reply related [flat|nested] 25+ messages in thread
* Re: [PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON
2019-06-11 10:51 ` [PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON Bitan Biswas
@ 2019-06-11 11:38 ` Dmitry Osipenko
0 siblings, 0 replies; 25+ messages in thread
From: Dmitry Osipenko @ 2019-06-11 11:38 UTC (permalink / raw)
To: Bitan Biswas, Laxman Dewangan, Thierry Reding, Jonathan Hunter,
linux-i2c, linux-tegra, linux-kernel, Peter Rosin, Wolfram Sang
Cc: Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
11.06.2019 13:51, Bitan Biswas пишет:
> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
> as needed. Remove BUG() and make Rx and Tx case handling
> similar. Add WARN_ON_ONCE check for non-zero rx_fifo_avail
> in tegra_i2c_empty_rx_fifo() and return new error
> I2C_ERR_UNEXPECTED_STATUS.
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> ---
Please see my answer to v4.
^ permalink raw reply [flat|nested] 25+ messages in thread
* Re: [PATCH V5 1/7] i2c: tegra: clean up macros
2019-06-11 10:51 [PATCH V5 1/7] i2c: tegra: clean up macros Bitan Biswas
` (5 preceding siblings ...)
2019-06-11 10:51 ` [PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON Bitan Biswas
@ 2019-06-12 10:21 ` Wolfram Sang
6 siblings, 0 replies; 25+ messages in thread
From: Wolfram Sang @ 2019-06-12 10:21 UTC (permalink / raw)
To: Bitan Biswas
Cc: Laxman Dewangan, Thierry Reding, Jonathan Hunter, linux-i2c,
linux-tegra, linux-kernel, Peter Rosin, Dmitry Osipenko,
Shardar Mohammed, Sowjanya Komatineni, Mantravadi Karthik
[-- Attachment #1: Type: text/plain, Size: 295 bytes --]
On Tue, Jun 11, 2019 at 03:51:08AM -0700, Bitan Biswas wrote:
> Clean up macros by:
> 1) removing unused macros
> 2) replace constants by macro BIT()
>
> Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Applied to for-next, thanks!
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 25+ messages in thread