[media] s5k5baf: allow to handle arbitrary long i2c sequences

Using variable length array in s5k5baf_write_arr_seq caused
an implicit assumption that i2c sequences should be short.
The patch rewrites the function so it can handle sequences
of any length and does not use variable length array.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/i2c/s5k5baf.c b/drivers/media/i2c/s5k5baf.c
index 4b8381111cbd2e66ef2cccc4be64c1e45106d161..77e10e0fd8d623fa78a0ca8e4688c9e44ab2ae10 100644 (file)
--- a/drivers/media/i2c/s5k5baf.c
+++ b/drivers/media/i2c/s5k5baf.c
@@ -478,25 +478,33 @@ static void s5k5baf_write_arr_seq(struct s5k5baf *state, u16 addr,
                                  u16 count, const u16 *seq)
 {
        struct i2c_client *c = v4l2_get_subdevdata(&state->sd);
-       __be16 buf[count + 1];
-       int ret, n;
+       __be16 buf[65];
 
        s5k5baf_i2c_write(state, REG_CMDWR_ADDR, addr);
        if (state->error)
                return;
 
+       v4l2_dbg(3, debug, c, "i2c_write_seq(count=%d): %*ph\n", count,
+                min(2 * count, 64), seq);
+
        buf[0] = __constant_cpu_to_be16(REG_CMD_BUF);
-       for (n = 1; n <= count; ++n)
-               buf[n] = cpu_to_be16(*seq++);
 
-       n *= 2;
-       ret = i2c_master_send(c, (char *)buf, n);
-       v4l2_dbg(3, debug, c, "i2c_write_seq(count=%d): %*ph\n", count,
-                min(2 * count, 64), seq - count);
+       while (count > 0) {
+               int n = min_t(int, count, ARRAY_SIZE(buf) - 1);
+               int ret, i;
 
-       if (ret != n) {
-               v4l2_err(c, "i2c_write_seq: error during transfer (%d)\n", ret);
-               state->error = ret;
+               for (i = 1; i <= n; ++i)
+                       buf[i] = cpu_to_be16(*seq++);
+
+               i *= 2;
+               ret = i2c_master_send(c, (char *)buf, i);
+               if (ret != i) {
+                       v4l2_err(c, "i2c_write_seq: error during transfer (%d)\n", ret);
+                       state->error = ret;
+                       break;
+               }
+
+               count -= n;
        }
 }