linux-kernel - [PATCH v2 3/3] leds: leds-lp5569: Enable chip after chip configuration

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Message-ID: <20240712004556.15601-3-ansuelsmth@gmail.com>
Date: Fri, 12 Jul 2024 02:45:54 +0200
From: Christian Marangi <ansuelsmth@...il.com>
To: Pavel Machek <pavel@....cz>,
	Lee Jones <lee@...nel.org>,
	linux-leds@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Christian Marangi <ansuelsmth@...il.com>
Subject: [PATCH v2 3/3] leds: leds-lp5569: Enable chip after chip configuration

Documentation say that clock internal config needs to be set BEFORE chip
is enabled. Align code to this and move the CHIP enable after the CHIP
is configured.

While at it also make use of STATUS reg and check when STARTUP is
completed instead of sleep for 1-2 ms.

Signed-off-by: Christian Marangi <ansuelsmth@...il.com>
---
Changes v2:
- Fix compilation warning (u8 instead of int)

 drivers/leds/leds-lp5569.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/leds/leds-lp5569.c b/drivers/leds/leds-lp5569.c
index 2b4f358bc63a..313dbf80ddec 100644
--- a/drivers/leds/leds-lp5569.c
+++ b/drivers/leds/leds-lp5569.c
@@ -7,6 +7,7 @@
 #include <linux/delay.h>
 #include <linux/firmware.h>
 #include <linux/i2c.h>
+#include <linux/iopoll.h>
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
@@ -91,6 +92,8 @@
 #define LP5569_ENG2_MUX_ADDR		0xd0
 #define LP5569_ENG3_MUX_ADDR		0xe0
 
+#define LP5569_STARTUP_SLEEP		500
+
 #define LEDn_STATUS_FAULT(n, status)	((status) >> (n) & BIT(0))
 
 #define LP5569_DEFAULT_CONFIG \
@@ -168,14 +171,7 @@ static int lp5569_init_program_engine(struct lp55xx_chip *chip)
 static int lp5569_post_init_device(struct lp55xx_chip *chip)
 {
 	int ret;
-	int val;
-
-	ret = lp55xx_write(chip, LP5569_REG_ENABLE, LP5569_ENABLE);
-	if (ret)
-		return ret;
-
-	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
-	usleep_range(1000, 2000);
+	u8 val;
 
 	val = LP5569_DEFAULT_CONFIG;
 	val |= FIELD_PREP(LP5569_CP_MODE_MASK, chip->pdata->charge_pump_mode);
@@ -198,6 +194,13 @@ static int lp5569_post_init_device(struct lp55xx_chip *chip)
 			return ret;
 	}
 
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, LP5569_ENABLE);
+	if (ret)
+		return ret;
+
+	read_poll_timeout(lp55xx_read, ret, !(val & LP5569_STARTUP_BUSY),
+			  LP5569_STARTUP_SLEEP, LP5569_STARTUP_SLEEP * 10, false,
+			  chip, LP5569_REG_STATUS, &val);
 
 	return lp5569_init_program_engine(chip);
 }
-- 
2.45.2