leds: qcom-lpg: Propagate errors in .get_state() to the caller

.get_state() can return an error indication. Make use of it to propagate
failing hardware accesses.

Acked-by: Pavel Machek <[e-mail]>
Acked-by: Conor Dooley <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Uwe Kleine-König <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>

drivers/leds/rgb/leds-qcom-lpg.c

···
 
 	ret = regmap_read(lpg->map, chan->base + LPG_SIZE_CLK_REG, &val);
 	if (ret)
-		return 0;
+		return ret;
 
 	refclk = lpg_clk_rates[val & PWM_CLK_SELECT_MASK];
 	if (refclk) {
 		ret = regmap_read(lpg->map, chan->base + LPG_PREDIV_CLK_REG, &val);
 		if (ret)
-			return 0;
+			return ret;
 
 		pre_div = lpg_pre_divs[FIELD_GET(PWM_FREQ_PRE_DIV_MASK, val)];
 		m = FIELD_GET(PWM_FREQ_EXP_MASK, val);
 
 		ret = regmap_bulk_read(lpg->map, chan->base + PWM_VALUE_REG, &pwm_value, sizeof(pwm_value));
 		if (ret)
-			return 0;
+			return ret;
 
 		state->period = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * LPG_RESOLUTION * pre_div * (1 << m), refclk);
 		state->duty_cycle = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pwm_value * pre_div * (1 << m), refclk);
···
 
 	ret = regmap_read(lpg->map, chan->base + PWM_ENABLE_CONTROL_REG, &val);
 	if (ret)
-		return 0;
+		return ret;
 
 	state->enabled = FIELD_GET(LPG_ENABLE_CONTROL_OUTPUT, val);
 	state->polarity = PWM_POLARITY_NORMAL;