| Message ID | 20181111204426.tvsatfeb2mam3tkm@raspberrypi (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2] Input: matrix_keypad - check for errors from of_get_named_gpio() | expand |
Hi, On Sun, Nov 11, 2018 at 09:44:28PM +0100, Christian Hoff wrote: > "of_get_named_gpio()" returns a negative error value if it fails > and drivers should check for this. This missing check was now > added to the matrix_keypad driver. > > In my case "of_get_named_gpio()" returned -EPROBE_DEFER because > the referenced GPIOs belong to an I/O expander, which was not yet > probed at the point in time when the matrix_keypad driver was > loading. Because the driver did not check for errors from the > "of_get_named_gpio()" routine, it was assuming that "-EPROBE_DEFER" > is actually a GPIO number and continued as usual, which led to further > errors like this later on: > > WARNING: CPU: 3 PID: 167 at drivers/gpio/gpiolib.c:114 > gpio_to_desc+0xc8/0xd0 > invalid GPIO -517 > > Note that the "GPIO number" -517 in the error message above is > actually "-EPROBE_DEFER". > > As part of the patch a misleading error message "no platform data defined" > was also removed. This does not lead to information loss because the other > error paths in matrix_keypad_parse_dt() already print an error. > > Signed-off-by: Christian Hoff <christian_hoff@gmx.net> > Suggested-by: Sebastian Reichel <sre@kernel.org> > Cc: stable@vger.kernel.org > --- Looks good to me. Reviewed-by: Sebastian Reichel <sre@kernel.org> -- Sebastian > drivers/input/keyboard/matrix_keypad.c | 23 ++++++++++++++--------- > 1 file changed, 14 insertions(+), 9 deletions(-) > > diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c > index f51ae09596ef..403452ef00e6 100644 > --- a/drivers/input/keyboard/matrix_keypad.c > +++ b/drivers/input/keyboard/matrix_keypad.c > @@ -407,7 +407,7 @@ matrix_keypad_parse_dt(struct device *dev) > struct matrix_keypad_platform_data *pdata; > struct device_node *np = dev->of_node; > unsigned int *gpios; > - int i, nrow, ncol; > + int ret, i, nrow, ncol; > > if (!np) { > dev_err(dev, "device lacks DT data\n"); > @@ -452,12 +452,19 @@ matrix_keypad_parse_dt(struct device *dev) > return ERR_PTR(-ENOMEM); > } > > - for (i = 0; i < pdata->num_row_gpios; i++) > - gpios[i] = of_get_named_gpio(np, "row-gpios", i); > + for (i = 0; i < nrow; i++) { > + ret = of_get_named_gpio(np, "row-gpios", i); > + if (ret < 0) > + return ERR_PTR(ret); > + gpios[i] = ret; > + } > > - for (i = 0; i < pdata->num_col_gpios; i++) > - gpios[pdata->num_row_gpios + i] = > - of_get_named_gpio(np, "col-gpios", i); > + for (i = 0; i < ncol; i++) { > + ret = of_get_named_gpio(np, "col-gpios", i); > + if (ret < 0) > + return ERR_PTR(ret); > + gpios[nrow + i] = ret; > + } > > pdata->row_gpios = gpios; > pdata->col_gpios = &gpios[pdata->num_row_gpios]; > @@ -484,10 +491,8 @@ static int matrix_keypad_probe(struct platform_device *pdev) > pdata = dev_get_platdata(&pdev->dev); > if (!pdata) { > pdata = matrix_keypad_parse_dt(&pdev->dev); > - if (IS_ERR(pdata)) { > - dev_err(&pdev->dev, "no platform data defined\n"); > + if (IS_ERR(pdata)) > return PTR_ERR(pdata); > - } > } else if (!pdata->keymap_data) { > dev_err(&pdev->dev, "no keymap data defined\n"); > return -EINVAL; > -- > 2.16.1.2.g9d582f143 >
On Sun, Nov 11, 2018 at 09:44:28PM +0100, Christian Hoff wrote: > "of_get_named_gpio()" returns a negative error value if it fails > and drivers should check for this. This missing check was now > added to the matrix_keypad driver. > > In my case "of_get_named_gpio()" returned -EPROBE_DEFER because > the referenced GPIOs belong to an I/O expander, which was not yet > probed at the point in time when the matrix_keypad driver was > loading. Because the driver did not check for errors from the > "of_get_named_gpio()" routine, it was assuming that "-EPROBE_DEFER" > is actually a GPIO number and continued as usual, which led to further > errors like this later on: > > WARNING: CPU: 3 PID: 167 at drivers/gpio/gpiolib.c:114 > gpio_to_desc+0xc8/0xd0 > invalid GPIO -517 > > Note that the "GPIO number" -517 in the error message above is > actually "-EPROBE_DEFER". > > As part of the patch a misleading error message "no platform data defined" > was also removed. This does not lead to information loss because the other > error paths in matrix_keypad_parse_dt() already print an error. > > Signed-off-by: Christian Hoff <christian_hoff@gmx.net> > Suggested-by: Sebastian Reichel <sre@kernel.org> > Cc: stable@vger.kernel.org Applied, thank you. > --- > drivers/input/keyboard/matrix_keypad.c | 23 ++++++++++++++--------- > 1 file changed, 14 insertions(+), 9 deletions(-) > > diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c > index f51ae09596ef..403452ef00e6 100644 > --- a/drivers/input/keyboard/matrix_keypad.c > +++ b/drivers/input/keyboard/matrix_keypad.c > @@ -407,7 +407,7 @@ matrix_keypad_parse_dt(struct device *dev) > struct matrix_keypad_platform_data *pdata; > struct device_node *np = dev->of_node; > unsigned int *gpios; > - int i, nrow, ncol; > + int ret, i, nrow, ncol; > > if (!np) { > dev_err(dev, "device lacks DT data\n"); > @@ -452,12 +452,19 @@ matrix_keypad_parse_dt(struct device *dev) > return ERR_PTR(-ENOMEM); > } > > - for (i = 0; i < pdata->num_row_gpios; i++) > - gpios[i] = of_get_named_gpio(np, "row-gpios", i); > + for (i = 0; i < nrow; i++) { > + ret = of_get_named_gpio(np, "row-gpios", i); > + if (ret < 0) > + return ERR_PTR(ret); > + gpios[i] = ret; > + } > > - for (i = 0; i < pdata->num_col_gpios; i++) > - gpios[pdata->num_row_gpios + i] = > - of_get_named_gpio(np, "col-gpios", i); > + for (i = 0; i < ncol; i++) { > + ret = of_get_named_gpio(np, "col-gpios", i); > + if (ret < 0) > + return ERR_PTR(ret); > + gpios[nrow + i] = ret; > + } > > pdata->row_gpios = gpios; > pdata->col_gpios = &gpios[pdata->num_row_gpios]; > @@ -484,10 +491,8 @@ static int matrix_keypad_probe(struct platform_device *pdev) > pdata = dev_get_platdata(&pdev->dev); > if (!pdata) { > pdata = matrix_keypad_parse_dt(&pdev->dev); > - if (IS_ERR(pdata)) { > - dev_err(&pdev->dev, "no platform data defined\n"); > + if (IS_ERR(pdata)) > return PTR_ERR(pdata); > - } > } else if (!pdata->keymap_data) { > dev_err(&pdev->dev, "no keymap data defined\n"); > return -EINVAL; > -- > 2.16.1.2.g9d582f143 >
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c index f51ae09596ef..403452ef00e6 100644 --- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -407,7 +407,7 @@ matrix_keypad_parse_dt(struct device *dev) struct matrix_keypad_platform_data *pdata; struct device_node *np = dev->of_node; unsigned int *gpios; - int i, nrow, ncol; + int ret, i, nrow, ncol; if (!np) { dev_err(dev, "device lacks DT data\n"); @@ -452,12 +452,19 @@ matrix_keypad_parse_dt(struct device *dev) return ERR_PTR(-ENOMEM); } - for (i = 0; i < pdata->num_row_gpios; i++) - gpios[i] = of_get_named_gpio(np, "row-gpios", i); + for (i = 0; i < nrow; i++) { + ret = of_get_named_gpio(np, "row-gpios", i); + if (ret < 0) + return ERR_PTR(ret); + gpios[i] = ret; + } - for (i = 0; i < pdata->num_col_gpios; i++) - gpios[pdata->num_row_gpios + i] = - of_get_named_gpio(np, "col-gpios", i); + for (i = 0; i < ncol; i++) { + ret = of_get_named_gpio(np, "col-gpios", i); + if (ret < 0) + return ERR_PTR(ret); + gpios[nrow + i] = ret; + } pdata->row_gpios = gpios; pdata->col_gpios = &gpios[pdata->num_row_gpios]; @@ -484,10 +491,8 @@ static int matrix_keypad_probe(struct platform_device *pdev) pdata = dev_get_platdata(&pdev->dev); if (!pdata) { pdata = matrix_keypad_parse_dt(&pdev->dev); - if (IS_ERR(pdata)) { - dev_err(&pdev->dev, "no platform data defined\n"); + if (IS_ERR(pdata)) return PTR_ERR(pdata); - } } else if (!pdata->keymap_data) { dev_err(&pdev->dev, "no keymap data defined\n"); return -EINVAL;
"of_get_named_gpio()" returns a negative error value if it fails and drivers should check for this. This missing check was now added to the matrix_keypad driver. In my case "of_get_named_gpio()" returned -EPROBE_DEFER because the referenced GPIOs belong to an I/O expander, which was not yet probed at the point in time when the matrix_keypad driver was loading. Because the driver did not check for errors from the "of_get_named_gpio()" routine, it was assuming that "-EPROBE_DEFER" is actually a GPIO number and continued as usual, which led to further errors like this later on: WARNING: CPU: 3 PID: 167 at drivers/gpio/gpiolib.c:114 gpio_to_desc+0xc8/0xd0 invalid GPIO -517 Note that the "GPIO number" -517 in the error message above is actually "-EPROBE_DEFER". As part of the patch a misleading error message "no platform data defined" was also removed. This does not lead to information loss because the other error paths in matrix_keypad_parse_dt() already print an error. Signed-off-by: Christian Hoff <christian_hoff@gmx.net> Suggested-by: Sebastian Reichel <sre@kernel.org> Cc: stable@vger.kernel.org --- drivers/input/keyboard/matrix_keypad.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-)