| Message ID | 20210322073220.1637117-2-gwendal@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: sx9310: Support ACPI properties | expand |
On Mon, Mar 22, 2021 at 9:33 AM Gwendal Grignou <gwendal@chromium.org> wrote: > > With the current code, we want to read 4 entries from DT array > "semtech,combined-sensors". If there are less, we silently fail as > of_property_read_u32_array() returns -EOVERFLOW. > > First count the number of entries and if between 1 and 4, collect the > content of the array. > > Fixes: 5b19ca2c78a0 ("iio: sx9310: Set various settings from DT") > Signed-off-by: Gwendal Grignou <gwendal@chromium.org> > --- > Changes in v6: > Fix error in of_property_count_elems_of_size() argumnent: > Used ARRAY_SIZE(combined) [4] instead of sizeof(u32). > > Changes in v5: > new, split fixes from changes needed for ACPI support. > > drivers/iio/proximity/sx9310.c | 40 ++++++++++++++++++++++++---------- > 1 file changed, 28 insertions(+), 12 deletions(-) > > diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c > index 394c2afe0f233..289c76bb3b024 100644 > --- a/drivers/iio/proximity/sx9310.c > +++ b/drivers/iio/proximity/sx9310.c > @@ -1213,17 +1213,17 @@ static int sx9310_init_compensation(struct iio_dev *indio_dev) > } > > static const struct sx9310_reg_default * > -sx9310_get_default_reg(struct sx9310_data *data, int i, > +sx9310_get_default_reg(struct sx9310_data *data, int idx, > struct sx9310_reg_default *reg_def) > { > - int ret; > const struct device_node *np = data->client->dev.of_node; > - u32 combined[SX9310_NUM_CHANNELS] = { 4, 4, 4, 4 }; > + u32 combined[SX9310_NUM_CHANNELS]; > + u32 start = 0, raw = 0, pos = 0; > unsigned long comb_mask = 0; > + int ret, i, count; > const char *res; > - u32 start = 0, raw = 0, pos = 0; > > - memcpy(reg_def, &sx9310_default_regs[i], sizeof(*reg_def)); > + memcpy(reg_def, &sx9310_default_regs[idx], sizeof(*reg_def)); > if (!np) > return reg_def; > > @@ -1234,15 +1234,31 @@ sx9310_get_default_reg(struct sx9310_data *data, int i, > reg_def->def |= SX9310_REG_PROX_CTRL2_SHIELDEN_GROUND; > } > > - reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK; > - of_property_read_u32_array(np, "semtech,combined-sensors", > - combined, ARRAY_SIZE(combined)); > - for (i = 0; i < ARRAY_SIZE(combined); i++) { > - if (combined[i] <= SX9310_NUM_CHANNELS) > - comb_mask |= BIT(combined[i]); > + count = of_property_count_elems_of_size(np, "semtech,combined-sensors", > + sizeof(u32)); instead of doing this manual validation with arrays, why not take the error codes from of_property_read_u32_array() and check them? ret = of_property_read_u32_array(np, "semtech,combined-sensors", combined, ARRAY_SIZE(combined)); checking for ret < 0 looks sufficient; it should return an error code if the number of elements in the DT array isn't exactly ARRAY_SIZE(combined) but stepping back a bit, the current logic (before this patch) looks reasonably ok to me; albeit, it's a bit quirky; and may require some more explanation somewhere, also in the DT semtech,combined-sensors: $ref: /schemas/types.yaml#/definitions/uint32-array description: | List of which sensors are combined and represented by CS3. Possible values are - 3 - CS3 (internal) 0 1 - CS0 + CS1 1 2 - CS1 + CS2 (default) 0 1 2 3 - CS0 + CS1 + CS2 + CS3 items: enum: [ 0, 1, 2, 3 ] minItems: 1 maxItems: 4 i mean, if nothing is defined there, value is 4 for the elements that are not defined in the DT; but i think there may be a bug, in the fact that number of elements in the array must be 4 (no more, no less) that is, when reading the DT, it implies a variable array size of 1 to 4, which doesn't seem true in the code; maybe a better idea would be to use of_property_read_***variable***_u32_array() this would allow for a flexible array size; count = of_property_read_variable_u32_array(np, "semtech,combined-sensors", combined, 1, ARRAY_SIZE(combined)); // min 1 , max 4 elements // count must be int, so that if it is negative, the array doesn't loop; for (i = 0; i < count; i++) { if (combined[i] <= SX9310_NUM_CHANNELS) comb_mask |= BIT(combined[i]); } > + if (count > 0 && count <= ARRAY_SIZE(combined)) { > + ret = of_property_read_u32_array(np, "semtech,combined-sensors", > + combined, count); > + if (ret) > + break; > + } else { > + /* > + * Either the property does not exist in the DT or the > + * number of entries is incorrect. > + */ > + break; > + } > + for (i = 0; i < count; i++) { > + if (combined[i] >= SX9310_NUM_CHANNELS) { > + /* Invalid sensor (invalid DT). */ > + break; > + } > + comb_mask |= BIT(combined[i]); > } > + if (i < count) > + break; > > - comb_mask &= 0xf; > + reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK; > if (comb_mask == (BIT(3) | BIT(2) | BIT(1) | BIT(0))) > reg_def->def |= SX9310_REG_PROX_CTRL2_COMBMODE_CS0_CS1_CS2_CS3; > else if (comb_mask == (BIT(1) | BIT(2))) > -- > 2.31.0.291.g576ba9dcdaf-goog >
On Mon, Mar 22, 2021 at 1:16 PM Alexandru Ardelean <ardeleanalex@gmail.com> wrote: > On Mon, Mar 22, 2021 at 9:33 AM Gwendal Grignou <gwendal@chromium.org> wrote: ... > but i think there may be a bug, in the fact that number of elements in > the array must be 4 (no more, no less) > that is, when reading the DT, it implies a variable array size of 1 to > 4, which doesn't seem true in the code; > > maybe a better idea would be to use of_property_read_***variable***_u32_array() > this would allow for a flexible array size; Wouldn't work in conjunction with the second patch. The above API is OF specific. > count = of_property_read_variable_u32_array(np, > "semtech,combined-sensors", > combined, 1, > ARRAY_SIZE(combined)); // min 1 , max 4 elements > // count must be int, so that if it is negative, the > array doesn't loop; > for (i = 0; i < count; i++) { > if (combined[i] <= SX9310_NUM_CHANNELS) > comb_mask |= BIT(combined[i]); > } >
On Mon, Mar 22, 2021 at 3:29 PM Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > On Mon, Mar 22, 2021 at 1:16 PM Alexandru Ardelean > <ardeleanalex@gmail.com> wrote: > > On Mon, Mar 22, 2021 at 9:33 AM Gwendal Grignou <gwendal@chromium.org> wrote: > > ... > > > but i think there may be a bug, in the fact that number of elements in > > the array must be 4 (no more, no less) > > that is, when reading the DT, it implies a variable array size of 1 to > > 4, which doesn't seem true in the code; > > > > maybe a better idea would be to use of_property_read_***variable***_u32_array() > > this would allow for a flexible array size; > > Wouldn't work in conjunction with the second patch. > The above API is OF specific. oh good point > > > count = of_property_read_variable_u32_array(np, > > "semtech,combined-sensors", > > combined, 1, > > ARRAY_SIZE(combined)); // min 1 , max 4 elements > > // count must be int, so that if it is negative, the > > array doesn't loop; > > for (i = 0; i < count; i++) { > > if (combined[i] <= SX9310_NUM_CHANNELS) > > comb_mask |= BIT(combined[i]); > > } > > > > -- > With Best Regards, > Andy Shevchenko
diff --git a/drivers/iio/proximity/sx9310.c b/drivers/iio/proximity/sx9310.c index 394c2afe0f233..289c76bb3b024 100644 --- a/drivers/iio/proximity/sx9310.c +++ b/drivers/iio/proximity/sx9310.c @@ -1213,17 +1213,17 @@ static int sx9310_init_compensation(struct iio_dev *indio_dev) } static const struct sx9310_reg_default * -sx9310_get_default_reg(struct sx9310_data *data, int i, +sx9310_get_default_reg(struct sx9310_data *data, int idx, struct sx9310_reg_default *reg_def) { - int ret; const struct device_node *np = data->client->dev.of_node; - u32 combined[SX9310_NUM_CHANNELS] = { 4, 4, 4, 4 }; + u32 combined[SX9310_NUM_CHANNELS]; + u32 start = 0, raw = 0, pos = 0; unsigned long comb_mask = 0; + int ret, i, count; const char *res; - u32 start = 0, raw = 0, pos = 0; - memcpy(reg_def, &sx9310_default_regs[i], sizeof(*reg_def)); + memcpy(reg_def, &sx9310_default_regs[idx], sizeof(*reg_def)); if (!np) return reg_def; @@ -1234,15 +1234,31 @@ sx9310_get_default_reg(struct sx9310_data *data, int i, reg_def->def |= SX9310_REG_PROX_CTRL2_SHIELDEN_GROUND; } - reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK; - of_property_read_u32_array(np, "semtech,combined-sensors", - combined, ARRAY_SIZE(combined)); - for (i = 0; i < ARRAY_SIZE(combined); i++) { - if (combined[i] <= SX9310_NUM_CHANNELS) - comb_mask |= BIT(combined[i]); + count = of_property_count_elems_of_size(np, "semtech,combined-sensors", + sizeof(u32)); + if (count > 0 && count <= ARRAY_SIZE(combined)) { + ret = of_property_read_u32_array(np, "semtech,combined-sensors", + combined, count); + if (ret) + break; + } else { + /* + * Either the property does not exist in the DT or the + * number of entries is incorrect. + */ + break; + } + for (i = 0; i < count; i++) { + if (combined[i] >= SX9310_NUM_CHANNELS) { + /* Invalid sensor (invalid DT). */ + break; + } + comb_mask |= BIT(combined[i]); } + if (i < count) + break; - comb_mask &= 0xf; + reg_def->def &= ~SX9310_REG_PROX_CTRL2_COMBMODE_MASK; if (comb_mask == (BIT(3) | BIT(2) | BIT(1) | BIT(0))) reg_def->def |= SX9310_REG_PROX_CTRL2_COMBMODE_CS0_CS1_CS2_CS3; else if (comb_mask == (BIT(1) | BIT(2)))
With the current code, we want to read 4 entries from DT array "semtech,combined-sensors". If there are less, we silently fail as of_property_read_u32_array() returns -EOVERFLOW. First count the number of entries and if between 1 and 4, collect the content of the array. Fixes: 5b19ca2c78a0 ("iio: sx9310: Set various settings from DT") Signed-off-by: Gwendal Grignou <gwendal@chromium.org> --- Changes in v6: Fix error in of_property_count_elems_of_size() argumnent: Used ARRAY_SIZE(combined) [4] instead of sizeof(u32). Changes in v5: new, split fixes from changes needed for ACPI support. drivers/iio/proximity/sx9310.c | 40 ++++++++++++++++++++++++---------- 1 file changed, 28 insertions(+), 12 deletions(-)