| Message ID | 20201026174126.19449-1-andriy.shevchenko@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] Input: edt-ft5x06 - use U16_MAX instead of -1 | expand |
On Mon, Oct 26, 2020 at 07:41:26PM +0200, Andy Shevchenko wrote: > Explicitly show what the value we supply for the touchscreen resolution > when it can't be detected. -1 is hard to compare with when unsigned short > type is in use. The change will help to avoid signed vs. unsigned error > prone comparisons. Any comments on this? -- With Best Regards, Andy Shevchenko
Hi Andy, On Mon, Oct 26, 2020 at 07:41:26PM +0200, Andy Shevchenko wrote: > Explicitly show what the value we supply for the touchscreen resolution > when it can't be detected. -1 is hard to compare with when unsigned short > type is in use. The change will help to avoid signed vs. unsigned error > prone comparisons. > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > v2: rebased on top of v5.10-rc1 > drivers/input/touchscreen/edt-ft5x06.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c > index 6ff81d48da86..34e9cb9c0691 100644 > --- a/drivers/input/touchscreen/edt-ft5x06.c > +++ b/drivers/input/touchscreen/edt-ft5x06.c > @@ -23,6 +23,7 @@ > #include <linux/input/touchscreen.h> > #include <linux/irq.h> > #include <linux/kernel.h> > +#include <linux/limits.h> > #include <linux/module.h> > #include <linux/ratelimit.h> > #include <linux/regulator/consumer.h> > @@ -1005,8 +1006,8 @@ edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata) > tsdata->num_y = edt_ft5x06_register_read(tsdata, > reg_addr->reg_num_y); > } else { > - tsdata->num_x = -1; > - tsdata->num_y = -1; > + tsdata->num_x = U16_MAX; > + tsdata->num_y = U16_MAX; Here we do not really do any comparisons, and using -1 to set to maximum unsigned number is a common pattern... However I just CCed you on a patch that removes special handling for number of electrodes on select firmwares, so this patch will no longer be relevant. Thanks. -- Dmitry
diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c index 6ff81d48da86..34e9cb9c0691 100644 --- a/drivers/input/touchscreen/edt-ft5x06.c +++ b/drivers/input/touchscreen/edt-ft5x06.c @@ -23,6 +23,7 @@ #include <linux/input/touchscreen.h> #include <linux/irq.h> #include <linux/kernel.h> +#include <linux/limits.h> #include <linux/module.h> #include <linux/ratelimit.h> #include <linux/regulator/consumer.h> @@ -1005,8 +1006,8 @@ edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata) tsdata->num_y = edt_ft5x06_register_read(tsdata, reg_addr->reg_num_y); } else { - tsdata->num_x = -1; - tsdata->num_y = -1; + tsdata->num_x = U16_MAX; + tsdata->num_y = U16_MAX; } }
Explicitly show what the value we supply for the touchscreen resolution when it can't be detected. -1 is hard to compare with when unsigned short type is in use. The change will help to avoid signed vs. unsigned error prone comparisons. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> --- v2: rebased on top of v5.10-rc1 drivers/input/touchscreen/edt-ft5x06.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)