[PATCH v4 11/20] gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL

[Kent Gibson]

Add support for the GPIO_V2_LINE_SET_VALUES_IOCTL.

Signed-off-by: Kent Gibson <warthog...@gmail.com>
---
 drivers/gpio/gpiolib-cdev.c | 67 +++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index 04472c2b6678..de88b7a5ba0f 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -811,6 +811,71 @@ static long line_get_values(struct line *line, void __user 
*ip)
        return 0;
 }
 
+static long line_set_values_locked(struct line *line,
+                                  struct gpio_v2_line_values *lv)
+{
+       DECLARE_BITMAP(vals, GPIO_V2_LINES_MAX);
+       struct gpio_desc **descs;
+       int ret, i, didx, num_set = 0;
+
+       bitmap_zero(vals, GPIO_V2_LINES_MAX);
+       for (i = 0; i < line->num_descs; i++) {
+               if (lv->mask & BIT_ULL(i)) {
+                       if (!test_bit(FLAG_IS_OUT, &line->descs[i]->flags))
+                               return -EPERM;
+                       if (lv->bits & BIT_ULL(i))
+                               __set_bit(num_set, vals);
+                       num_set++;
+               }
+       }
+       if (num_set == 0)
+               return -EINVAL;
+
+       if (num_set == line->num_descs)
+               /* Reuse the array setting function */
+               return gpiod_set_array_value_complex(false,
+                                                    true,
+                                                    line->num_descs,
+                                                    line->descs,
+                                                    NULL,
+                                                    vals);
+
+       /* build compacted desc array and values */
+       descs = kmalloc_array(num_set, sizeof(*descs), GFP_KERNEL);
+       for (didx = 0, i = 0; i < line->num_descs; i++) {
+               if (lv->mask & BIT_ULL(i)) {
+                       descs[didx] = line->descs[i];
+                       didx++;
+               }
+       }
+       ret = gpiod_set_array_value_complex(false,
+                                           true,
+                                           num_set,
+                                           descs,
+                                           NULL,
+                                           vals);
+
+       kfree(descs);
+       return ret;
+}
+
+static long line_set_values(struct line *line, void __user *ip)
+{
+       struct gpio_v2_line_values lv;
+       int ret;
+
+       if (copy_from_user(&lv, ip, sizeof(lv)))
+               return -EFAULT;
+
+       mutex_lock(&line->config_mutex);
+
+       ret = line_set_values_locked(line, &lv);
+
+       mutex_unlock(&line->config_mutex);
+
+       return ret;
+}
+
 static long line_set_config_locked(struct line *line,
                                   struct gpio_v2_line_config *lc)
 {
@@ -880,6 +945,8 @@ static long line_ioctl(struct file *file, unsigned int cmd,
 
        if (cmd == GPIO_V2_LINE_GET_VALUES_IOCTL)
                return line_get_values(line, ip);
+       else if (cmd == GPIO_V2_LINE_SET_VALUES_IOCTL)
+               return line_set_values(line, ip);
        else if (cmd == GPIO_V2_LINE_SET_CONFIG_IOCTL)
                return line_set_config(line, ip);
 
-- 
2.28.0