[PATCH v2] backlight: Add backlight driver for Bachmann's ot200

[Andrew Morton]

On Wed, 01 Feb 2012 19:48:57 +0100

Add backlight driver for Bachmann's ot200 visualisation device. The
driver uses MFGPT 7 of CS5535 silicon to regulate the backlight.

Looks OK to me. A couple of little tweaks:

+++ a/drivers/video/backlight/ot200_bl.c
@@ -19,15 +19,15 @@
static struct cs5535_mfgpt_timer *pwm_timer;

/* this array defines the mapping of brightness in % to pwm frequency */
-static const u8 dim_table[101] = {0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
- 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4,
- 4, 5, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 9, 9,
- 10, 10, 11, 11, 12, 12, 13, 14, 15, 15, 16,
- 17, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28,
- 30, 31, 33, 35, 37, 39, 41, 43, 45, 47, 50,
- 53, 55, 58, 61, 65, 68, 72, 75, 79, 84, 88,
- 93, 97, 103, 108, 114, 120, 126, 133, 140,
- 147, 155, 163};
+static const u8 dim_table[101] = {0, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
+ 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4,
+ 4, 5, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 9, 9,
+ 10, 10, 11, 11, 12, 12, 13, 14, 15, 15, 16,
+ 17, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28,
+ 30, 31, 33, 35, 37, 39, 41, 43, 45, 47, 50,
+ 53, 55, 58, 61, 65, 68, 72, 75, 79, 84, 88,
+ 93, 97, 103, 108, 114, 120, 126, 133, 140,
+ 147, 155, 163};

struct ot200_backlight_data {
int current_brightness;
@@ -51,7 +51,7 @@ static int ot200_backlight_update_status
/* enable or disable PWM timer */
if (brightness == 0)
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_SETUP, 0);
- else if (brightness != 0 && data->current_brightness == 0) {
+ else if (data->current_brightness == 0) {
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_COUNTER, 0);
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_SETUP,
MFGPT_SETUP_CNTEN);
_