* [PATCH 1/1] input: mma8450: Add chip ID check in probe
@ 2024-12-13 22:23 Frank Li
2024-12-13 23:02 ` Uwe Kleine-König
0 siblings, 1 reply; 4+ messages in thread
From: Frank Li @ 2024-12-13 22:23 UTC (permalink / raw)
To: Dmitry Torokhov, Luwei Zhou, Vipul Kumar, Dong Aisheng,
Uwe Kleine-König,
open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...,
open list
Cc: imx
From: Luwei Zhou <b45643@freescale.com>
Prevent continuous polling error logs by adding a chip ID check in the
probe function. This ensures the driver only proceeds when the mma8450 is
present, avoiding issues in scenarios like missing add-on cards.
Signed-off-by: Luwei Zhou <b45643@freescale.com>
Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
drivers/input/misc/mma8450.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
index 08412239b8e69..da941748ed29b 100644
--- a/drivers/input/misc/mma8450.c
+++ b/drivers/input/misc/mma8450.c
@@ -38,6 +38,8 @@
#define MMA8450_CTRL_REG1 0x38
#define MMA8450_CTRL_REG2 0x39
+#define MMA8450_ID 0xc6
+#define MMA8450_WHO_AM_I 0x0f
static int mma8450_read(struct i2c_client *c, unsigned int off)
{
@@ -148,8 +150,20 @@ static void mma8450_close(struct input_dev *input)
*/
static int mma8450_probe(struct i2c_client *c)
{
+ struct i2c_adapter *adapter = to_i2c_adapter(c->dev.parent);
struct input_dev *input;
- int err;
+ int err, client_id;
+
+ err = i2c_check_functionality(adapter,
+ I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA);
+ if (!err)
+ return err;
+
+ client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
+ if (client_id != MMA8450_ID)
+ return dev_err_probe(&c->dev, -EINVAL,
+ "read chip ID 0x%x is not equal to 0x%x!\n",
+ client_id, MMA8450_ID);
input = devm_input_allocate_device(&c->dev);
if (!input)
--
2.34.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] input: mma8450: Add chip ID check in probe
2024-12-13 22:23 [PATCH 1/1] input: mma8450: Add chip ID check in probe Frank Li
@ 2024-12-13 23:02 ` Uwe Kleine-König
2024-12-16 16:30 ` Frank Li
0 siblings, 1 reply; 4+ messages in thread
From: Uwe Kleine-König @ 2024-12-13 23:02 UTC (permalink / raw)
To: Frank Li
Cc: Dmitry Torokhov, Luwei Zhou, Vipul Kumar, Dong Aisheng,
open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...,
open list, imx
[-- Attachment #1: Type: text/plain, Size: 2093 bytes --]
Hello Frank,
On Fri, Dec 13, 2024 at 05:23:09PM -0500, Frank Li wrote:
> From: Luwei Zhou <b45643@freescale.com>
>
> Prevent continuous polling error logs by adding a chip ID check in the
> probe function. This ensures the driver only proceeds when the mma8450 is
> present, avoiding issues in scenarios like missing add-on cards.
>
> Signed-off-by: Luwei Zhou <b45643@freescale.com>
> Signed-off-by: Fugang Duan <B38611@freescale.com>
> Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> drivers/input/misc/mma8450.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
> index 08412239b8e69..da941748ed29b 100644
> --- a/drivers/input/misc/mma8450.c
> +++ b/drivers/input/misc/mma8450.c
> @@ -38,6 +38,8 @@
>
> #define MMA8450_CTRL_REG1 0x38
> #define MMA8450_CTRL_REG2 0x39
> +#define MMA8450_ID 0xc6
> +#define MMA8450_WHO_AM_I 0x0f
>
> static int mma8450_read(struct i2c_client *c, unsigned int off)
> {
> @@ -148,8 +150,20 @@ static void mma8450_close(struct input_dev *input)
> */
> static int mma8450_probe(struct i2c_client *c)
> {
> + struct i2c_adapter *adapter = to_i2c_adapter(c->dev.parent);
+ struct i2c_adapter *adapter = c->adapter;
> struct input_dev *input;
> - int err;
> + int err, client_id;
> +
> + err = i2c_check_functionality(adapter,
> + I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA);
> + if (!err)
> + return err;
How unusual. I would have expected no ! here.
> + client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
> + if (client_id != MMA8450_ID)
> + return dev_err_probe(&c->dev, -EINVAL,
> + "read chip ID 0x%x is not equal to 0x%x!\n",
> + client_id, MMA8450_ID);
Given that here you emit an error message, maybe add an error message
above, too?
> input = devm_input_allocate_device(&c->dev);
> if (!input)
Best regards
Uwe
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] input: mma8450: Add chip ID check in probe
2024-12-13 23:02 ` Uwe Kleine-König
@ 2024-12-16 16:30 ` Frank Li
2024-12-16 17:14 ` Dmitry Torokhov
0 siblings, 1 reply; 4+ messages in thread
From: Frank Li @ 2024-12-16 16:30 UTC (permalink / raw)
To: Uwe Kleine-König
Cc: Dmitry Torokhov, Luwei Zhou, Vipul Kumar, Dong Aisheng,
open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...,
open list, imx
On Sat, Dec 14, 2024 at 12:02:56AM +0100, Uwe Kleine-König wrote:
> Hello Frank,
>
> On Fri, Dec 13, 2024 at 05:23:09PM -0500, Frank Li wrote:
> > From: Luwei Zhou <b45643@freescale.com>
> >
> > Prevent continuous polling error logs by adding a chip ID check in the
> > probe function. This ensures the driver only proceeds when the mma8450 is
> > present, avoiding issues in scenarios like missing add-on cards.
> >
> > Signed-off-by: Luwei Zhou <b45643@freescale.com>
> > Signed-off-by: Fugang Duan <B38611@freescale.com>
> > Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
> > Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > ---
> > drivers/input/misc/mma8450.c | 16 +++++++++++++++-
> > 1 file changed, 15 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
> > index 08412239b8e69..da941748ed29b 100644
> > --- a/drivers/input/misc/mma8450.c
> > +++ b/drivers/input/misc/mma8450.c
> > @@ -38,6 +38,8 @@
> >
> > #define MMA8450_CTRL_REG1 0x38
> > #define MMA8450_CTRL_REG2 0x39
> > +#define MMA8450_ID 0xc6
> > +#define MMA8450_WHO_AM_I 0x0f
> >
> > static int mma8450_read(struct i2c_client *c, unsigned int off)
> > {
> > @@ -148,8 +150,20 @@ static void mma8450_close(struct input_dev *input)
> > */
> > static int mma8450_probe(struct i2c_client *c)
> > {
> > + struct i2c_adapter *adapter = to_i2c_adapter(c->dev.parent);
>
> + struct i2c_adapter *adapter = c->adapter;
>
> > struct input_dev *input;
> > - int err;
> > + int err, client_id;
> > +
> > + err = i2c_check_functionality(adapter,
> > + I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA);
> > + if (!err)
> > + return err;
>
> How unusual. I would have expected no ! here.
yes, it should be better
if (!i2c_check_functionality())
....
i2c_check_functionality() return 1 if adapter supports everything we need.
Frank
>
> > + client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
> > + if (client_id != MMA8450_ID)
> > + return dev_err_probe(&c->dev, -EINVAL,
> > + "read chip ID 0x%x is not equal to 0x%x!\n",
> > + client_id, MMA8450_ID);
>
> Given that here you emit an error message, maybe add an error message
> above, too?
>
> > input = devm_input_allocate_device(&c->dev);
> > if (!input)
>
> Best regards
> Uwe
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] input: mma8450: Add chip ID check in probe
2024-12-16 16:30 ` Frank Li
@ 2024-12-16 17:14 ` Dmitry Torokhov
0 siblings, 0 replies; 4+ messages in thread
From: Dmitry Torokhov @ 2024-12-16 17:14 UTC (permalink / raw)
To: Frank Li
Cc: Uwe Kleine-König, Luwei Zhou, Vipul Kumar, Dong Aisheng,
open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...,
open list, imx
On Mon, Dec 16, 2024 at 11:30:15AM -0500, Frank Li wrote:
> On Sat, Dec 14, 2024 at 12:02:56AM +0100, Uwe Kleine-König wrote:
> > Hello Frank,
> >
> > On Fri, Dec 13, 2024 at 05:23:09PM -0500, Frank Li wrote:
> > > From: Luwei Zhou <b45643@freescale.com>
> > >
> > > Prevent continuous polling error logs by adding a chip ID check in the
> > > probe function. This ensures the driver only proceeds when the mma8450 is
> > > present, avoiding issues in scenarios like missing add-on cards.
> > >
> > > Signed-off-by: Luwei Zhou <b45643@freescale.com>
> > > Signed-off-by: Fugang Duan <B38611@freescale.com>
> > > Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
> > > Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > > drivers/input/misc/mma8450.c | 16 +++++++++++++++-
> > > 1 file changed, 15 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
> > > index 08412239b8e69..da941748ed29b 100644
> > > --- a/drivers/input/misc/mma8450.c
> > > +++ b/drivers/input/misc/mma8450.c
> > > @@ -38,6 +38,8 @@
> > >
> > > #define MMA8450_CTRL_REG1 0x38
> > > #define MMA8450_CTRL_REG2 0x39
> > > +#define MMA8450_ID 0xc6
> > > +#define MMA8450_WHO_AM_I 0x0f
> > >
> > > static int mma8450_read(struct i2c_client *c, unsigned int off)
> > > {
> > > @@ -148,8 +150,20 @@ static void mma8450_close(struct input_dev *input)
> > > */
> > > static int mma8450_probe(struct i2c_client *c)
> > > {
> > > + struct i2c_adapter *adapter = to_i2c_adapter(c->dev.parent);
> >
> > + struct i2c_adapter *adapter = c->adapter;
> >
> > > struct input_dev *input;
> > > - int err;
> > > + int err, client_id;
> > > +
> > > + err = i2c_check_functionality(adapter,
> > > + I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA);
> > > + if (!err)
> > > + return err;
> >
> > How unusual. I would have expected no ! here.
>
> yes, it should be better
>
> if (!i2c_check_functionality())
> ....
>
> i2c_check_functionality() return 1 if adapter supports everything we need.
Yes, it would be much better, otherwise in the case when an adapter does
not support the required functionality your code returns 0 which signals
successful probing.
Thanks.
--
Dmitry
^ permalink raw reply [flat|nested] 4+ messages in thread
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2024-12-13 22:23 [PATCH 1/1] input: mma8450: Add chip ID check in probe Frank Li
2024-12-13 23:02 ` Uwe Kleine-König
2024-12-16 16:30 ` Frank Li
2024-12-16 17:14 ` Dmitry Torokhov
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