gpio: aggregator: Wrap access to gpiochip_fwd.tmp[]

The tmp[] member of the gpiochip_fwd structure is used to store both the
temporary values bitmap and the desc pointers for operations on multiple
GPIOs.  As both are arrays with sizes unknown at compile-time, accessing
them requires offset calculations, which are currently duplicated in
gpio_fwd_get_multiple() and gpio_fwd_set_multiple().

Introduce (a) accessors for both arrays and (b) a macro to calculate the
needed storage size.  This confines the layout of the tmp[] member into
a single spot, to ease maintenance.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
This commit is contained in:
Geert Uytterhoeven 2021-10-04 14:45:45 +02:00 committed by Bartosz Golaszewski
parent 7687a5b0ee
commit aa4858eb82

View File

@ -247,6 +247,11 @@ struct gpiochip_fwd {
unsigned long tmp[]; /* values and descs for multiple ops */
};
#define fwd_tmp_values(fwd) &(fwd)->tmp[0]
#define fwd_tmp_descs(fwd) (void *)&(fwd)->tmp[BITS_TO_LONGS((fwd)->chip.ngpio)]
#define fwd_tmp_size(ngpios) (BITS_TO_LONGS((ngpios)) + (ngpios))
static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
{
struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
@ -279,15 +284,11 @@ static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
static int gpio_fwd_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
unsigned long *bits)
{
struct gpio_desc **descs;
unsigned long *values;
struct gpio_desc **descs = fwd_tmp_descs(fwd);
unsigned long *values = fwd_tmp_values(fwd);
unsigned int i, j = 0;
int error;
/* Both values bitmap and desc pointers are stored in tmp[] */
values = &fwd->tmp[0];
descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
bitmap_clear(values, 0, fwd->chip.ngpio);
for_each_set_bit(i, mask, fwd->chip.ngpio)
descs[j++] = fwd->descs[i];
@ -333,14 +334,10 @@ static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
static void gpio_fwd_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
unsigned long *bits)
{
struct gpio_desc **descs;
unsigned long *values;
struct gpio_desc **descs = fwd_tmp_descs(fwd);
unsigned long *values = fwd_tmp_values(fwd);
unsigned int i, j = 0;
/* Both values bitmap and desc pointers are stored in tmp[] */
values = &fwd->tmp[0];
descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
for_each_set_bit(i, mask, fwd->chip.ngpio) {
__assign_bit(j, values, test_bit(i, bits));
descs[j++] = fwd->descs[i];
@ -398,8 +395,8 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
unsigned int i;
int error;
fwd = devm_kzalloc(dev, struct_size(fwd, tmp,
BITS_TO_LONGS(ngpios) + ngpios), GFP_KERNEL);
fwd = devm_kzalloc(dev, struct_size(fwd, tmp, fwd_tmp_size(ngpios)),
GFP_KERNEL);
if (!fwd)
return ERR_PTR(-ENOMEM);