[PATCH v8 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 | 61 +++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index b6da92d9dba1..12d5c6543c15 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -779,6 +779,65 @@ static long linereq_get_values(struct linereq *lr, void 
__user *ip)
        return 0;
 }
 
+static long linereq_set_values_unlocked(struct linereq *lr,
+                                       struct gpio_v2_line_values *lv)
+{
+       DECLARE_BITMAP(vals, 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;
+               }
+       }
+       if (num_set == 0)
+               return -EINVAL;
+
+       if (num_set != 1) {
+               /* 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++;
+                       }
+               }
+       }
+       ret = gpiod_set_array_value_complex(false, true, num_set,
+                                           descs, NULL, vals);
+
+       if (num_set != 1)
+               kfree(descs);
+       return ret;
+}
+
+static long linereq_set_values(struct linereq *lr, void __user *ip)
+{
+       struct gpio_v2_line_values lv;
+       int ret;
+
+       if (copy_from_user(&lv, ip, sizeof(lv)))
+               return -EFAULT;
+
+       mutex_lock(&lr->config_mutex);
+
+       ret = linereq_set_values_unlocked(lr, &lv);
+
+       mutex_unlock(&lr->config_mutex);
+
+       return ret;
+}
+
 static long linereq_set_config_unlocked(struct linereq *lr,
                                        struct gpio_v2_line_config *lc)
 {
@@ -855,6 +914,8 @@ static long linereq_ioctl(struct file *file, unsigned int 
cmd,
 
        if (cmd == GPIO_V2_LINE_GET_VALUES_IOCTL)
                return linereq_get_values(lr, ip);
+       else if (cmd == GPIO_V2_LINE_SET_VALUES_IOCTL)
+               return linereq_set_values(lr, ip);
        else if (cmd == GPIO_V2_LINE_SET_CONFIG_IOCTL)
                return linereq_set_config(lr, ip);
 
-- 
2.28.0