[PATCH v1 5/5] gpiolib: cdev: Utilize more bitmap APIs

Andy Shevchenko
2023-09-26T05:20:55Z

Currently we have a few bitmap calls that are open coded in the library
module. Let's convert them to use generic bitmap APIs instead.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/gpio/gpiolib-cdev.c | 79 +++++++++++++++++--------------------
1 file changed, 36 insertions(+), 43 deletions(-)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index e39d344feb28..a5bbbd44531f 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -1263,35 +1263,32 @@ static long linereq_get_values(struct linereq *lr, void __user *ip)
{
struct gpio_v2_line_values lv;
DECLARE_BITMAP(vals, GPIO_V2_LINES_MAX);
+ DECLARE_BITMAP(mask, GPIO_V2_LINES_MAX);
+ DECLARE_BITMAP(bits, GPIO_V2_LINES_MAX);
struct gpio_desc **descs;
unsigned int i, didx, num_get;
- bool val;
int ret;

/* NOTE: It's ok to read values of output lines. */
if (copy_from_user(&lv, ip, sizeof(lv)))
return -EFAULT;

- for (num_get = 0, i = 0; i < lr->num_lines; i++) {
- if (lv.mask & BIT_ULL(i)) {
- num_get++;
- descs = &lr->lines[i].desc;
- }
- }
+ bitmap_from_arr64(mask, &lv.mask, GPIO_V2_LINES_MAX);

+ num_get = bitmap_weight(mask, lr->num_lines);
if (num_get == 0)
return -EINVAL;

- if (num_get != 1) {
+ if (num_get == 1) {
+ descs = &lr->lines[find_first_bit(mask, lr->num_lines)].desc;
+ } else {
descs = kmalloc_array(num_get, sizeof(*descs), GFP_KERNEL);
if (!descs)
return -ENOMEM;
- for (didx = 0, i = 0; i < lr->num_lines; i++) {
- if (lv.mask & BIT_ULL(i)) {
- descs[didx] = lr->lines[i].desc;
- didx++;
- }
- }
+
+ didx = 0;
+ for_each_set_bit(i, mask, lr->num_lines)
+ descs[didx++] = lr->lines[i].desc;
}
ret = gpiod_get_array_value_complex(false, true, num_get,
descs, NULL, vals);
@@ -1301,19 +1298,15 @@ static long linereq_get_values(struct linereq *lr, void __user *ip)
if (ret)
return ret;

- lv.bits = 0;
- for (didx = 0, i = 0; i < lr->num_lines; i++) {
- if (lv.mask & BIT_ULL(i)) {
- if (lr->lines[i].sw_debounced)
- val = debounced_value(&lr->lines[i]);
- else
- val = test_bit(didx, vals);
- if (val)
- lv.bits |= BIT_ULL(i);
- didx++;
- }
+ bitmap_scatter(bits, vals, mask, lr->num_lines);
+
+ for_each_set_bit(i, mask, lr->num_lines) {
+ if (lr->lines[i].sw_debounced)
+ __assign_bit(i, bits, debounced_value(&lr->lines[i]));
}

+ bitmap_to_arr64(&lv.bits, bits, GPIO_V2_LINES_MAX);
+
if (copy_to_user(ip, &lv, sizeof(lv)))
return -EFAULT;

@@ -1324,35 +1317,35 @@ static long linereq_set_values_unlocked(struct linereq *lr,
struct gpio_v2_line_values *lv)
{
DECLARE_BITMAP(vals, GPIO_V2_LINES_MAX);
+ DECLARE_BITMAP(mask, GPIO_V2_LINES_MAX);
+ DECLARE_BITMAP(bits, GPIO_V2_LINES_MAX);
struct gpio_desc **descs;
unsigned int i, didx, num_set;
int ret;

- bitmap_zero(vals, GPIO_V2_LINES_MAX);
- for (num_set = 0, i = 0; i < lr->num_lines; i++) {
- if (lv->mask & BIT_ULL(i)) {
- if (!test_bit(FLAG_IS_OUT, &lr->lines[i].desc->flags))
- return -EPERM;
- if (lv->bits & BIT_ULL(i))
- __set_bit(num_set, vals);
- num_set++;
- descs = &lr->lines[i].desc;
- }
- }
+ bitmap_from_arr64(mask, &lv->mask, GPIO_V2_LINES_MAX);
+ bitmap_from_arr64(bits, &lv->bits, GPIO_V2_LINES_MAX);
+
+ num_set = bitmap_gather(vals, bits, mask, lr->num_lines);
if (num_set == 0)
return -EINVAL;

- if (num_set != 1) {
+ for_each_set_bit(i, mask, lr->num_lines) {
+ if (!test_bit(FLAG_IS_OUT, &lr->lines[i].desc->flags))
+ return -EPERM;
+ }
+
+ if (num_set == 1) {
+ descs = &lr->lines[find_first_bit(mask, lr->num_lines)].desc;
+ } else {
/* build compacted desc array and values */
descs = kmalloc_array(num_set, sizeof(*descs), GFP_KERNEL);
if (!descs)
return -ENOMEM;
- for (didx = 0, i = 0; i < lr->num_lines; i++) {
- if (lv->mask & BIT_ULL(i)) {
- descs[didx] = lr->lines[i].desc;
- didx++;
- }
- }
+
+ didx = 0;
+ for_each_set_bit(i, mask, lr->num_lines)
+ descs[didx++] = lr->lines[i].desc;
}
ret = gpiod_set_array_value_complex(false, true, num_set,
descs, NULL, vals);
--
2.40.0.1.gaa8946217a0b