Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752279AbbKBFCQ (ORCPT ); Mon, 2 Nov 2015 00:02:16 -0500 Received: from devils.ext.ti.com ([198.47.26.153]:60313 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751910AbbKBFCJ (ORCPT ); Mon, 2 Nov 2015 00:02:09 -0500 From: Milo Kim To: , , CC: Milo Kim , Jingoo Han Subject: [PATCH 08/16] backlight: ti-lmu-backlight: add LM3532 driver Date: Mon, 2 Nov 2015 14:01:15 +0900 Message-ID: <1446440483-6948-9-git-send-email-milo.kim@ti.com> X-Mailer: git-send-email 1.9.5.msysgit.0 In-Reply-To: <1446440483-6948-8-git-send-email-milo.kim@ti.com> References: <1446440483-6948-1-git-send-email-milo.kim@ti.com> <1446440483-6948-2-git-send-email-milo.kim@ti.com> <1446440483-6948-3-git-send-email-milo.kim@ti.com> <1446440483-6948-4-git-send-email-milo.kim@ti.com> <1446440483-6948-5-git-send-email-milo.kim@ti.com> <1446440483-6948-6-git-send-email-milo.kim@ti.com> <1446440483-6948-7-git-send-email-milo.kim@ti.com> <1446440483-6948-8-git-send-email-milo.kim@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7388 Lines: 246 LM3532 has 3 backlight strings and 8 bit dimming is supported. PWM brightness control is also supported. Common backlight driver is controlled by TI LMU backlight driver. Only LM3532 specific code is implemented here. Cc: Jingoo Han Cc: Lee Jones Cc: linux-kernel@vger.kernel.org Signed-off-by: Milo Kim --- drivers/video/backlight/Kconfig | 9 ++ drivers/video/backlight/Makefile | 1 + drivers/video/backlight/lm3532_bl.c | 183 ++++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 drivers/video/backlight/lm3532_bl.c diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index f26eb1c..86d7946 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -390,6 +390,15 @@ config BACKLIGHT_LM3639 help This supports TI LM3639 Backlight + 1.5A Flash LED Driver +config BACKLIGHT_LM3532 + tristate "Backlight driver for TI LM3532" + depends on BACKLIGHT_CLASS_DEVICE && MFD_TI_LMU + select TI_LMU_BACKLIGHT + help + Say Y to enable the backlight driver for TI LM3532. + Up to 3 backlight strings and 8 bit dimming is supported. + PWM brightness control is also supported. + config TI_LMU_BACKLIGHT tristate "Backlight driver for TI LMU" depends on BACKLIGHT_LM3532 || BACKLIGHT_LM3631 || \ diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 9e475dc..e037f57 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_BACKLIGHT_GPIO) += gpio_backlight.o obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o +obj-$(CONFIG_BACKLIGHT_LM3532) += lm3532_bl.o obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o obj-$(CONFIG_BACKLIGHT_LM3639) += lm3639_bl.o diff --git a/drivers/video/backlight/lm3532_bl.c b/drivers/video/backlight/lm3532_bl.c new file mode 100644 index 0000000..fd21a3c --- /dev/null +++ b/drivers/video/backlight/lm3532_bl.c @@ -0,0 +1,183 @@ +/* + * TI LM3532 Backlight Driver + * + * Copyright 2015 Texas Instruments + * + * Author: Milo Kim + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include + +#include "ti-lmu-backlight.h" + +#define LM3532_PWM1 0 +#define LM3532_BL_MAX_STRINGS 3 +#define LM3532_MAX_ZONE_CFG 3 +#define LM3532_MAX_BRIGHTNESS 255 + +static int lm3532_bl_init(struct ti_lmu_bl_chip *chip) +{ + int i, ret; + u8 lm3532_regs[] = { LM3532_REG_ZONE_CFG_A, LM3532_REG_ZONE_CFG_B, + LM3532_REG_ZONE_CFG_C, }; + + /* + * Assign zone targets as below. + * Zone target 0 for control A + * Zone target 1 for control B + * Zone target 2 for control C + */ + + for (i = 0; i < LM3532_MAX_ZONE_CFG; i++) { + ret = ti_lmu_update_bits(chip->lmu, lm3532_regs[i], + LM3532_ZONE_CFG_MASK, + i << LM3532_ZONE_CFG_SHIFT); + if (ret) + return ret; + } + + return 0; +} + +static int lm3532_bl_enable(struct ti_lmu_bl *lmu_bl, int enable) +{ + return ti_lmu_update_bits(lmu_bl->chip->lmu, LM3532_REG_ENABLE, + BIT(lmu_bl->bank_id), + enable << lmu_bl->bank_id); +} + +static int lm3532_bl_set_brightness(struct ti_lmu_bl *lmu_bl, int brightness) +{ + u8 reg[] = { LM3532_REG_BRT_A, LM3532_REG_BRT_B, LM3532_REG_BRT_C, }; + + return ti_lmu_write_byte(lmu_bl->chip->lmu, reg[lmu_bl->bank_id], + brightness); +} + +static int lm3532_bl_select_pwm_bank(struct ti_lmu_bl *lmu_bl, int bank_id) +{ + struct ti_lmu *lmu = lmu_bl->chip->lmu; + u8 mask[] = { LM3532_PWM_SEL_A_MASK, LM3532_PWM_SEL_B_MASK, + LM3532_PWM_SEL_C_MASK, }; + u8 shift[] = { LM3532_PWM_SEL_A_SHIFT, LM3532_PWM_SEL_B_SHIFT, + LM3532_PWM_SEL_C_SHIFT, }; + + /* Limitation: only PWM1 is supported. PWM2 is not supported. */ + + return ti_lmu_update_bits(lmu, LM3532_REG_PWM_CFG_BASE + bank_id, + mask[bank_id], + (1 << shift[bank_id]) | LM3532_PWM1); +} + +static int lm3532_bl_string_configure(struct ti_lmu_bl *lmu_bl) +{ + struct ti_lmu *lmu = lmu_bl->chip->lmu; + int bank_id = lmu_bl->bank_id; + int is_detected = 0; + int i, ret; + u8 mask[] = { LM3532_ILED1_CFG_MASK, LM3532_ILED2_CFG_MASK, + LM3532_ILED3_CFG_MASK, }; + u8 shift[] = { LM3532_ILED1_CFG_SHIFT, LM3532_ILED2_CFG_SHIFT, + LM3532_ILED3_CFG_SHIFT, }; + + /* Assign control bank from backlight string configuration */ + for (i = 0; i < LM3532_BL_MAX_STRINGS; i++) { + if (test_bit(i, &lmu_bl->bl_string)) { + ret = ti_lmu_update_bits(lmu, LM3532_REG_OUTPUT_CFG, + mask[i], bank_id << shift[i]); + if (ret) + return ret; + + is_detected = 1; + } + } + + if (!is_detected) { + dev_err(lmu_bl->chip->dev, "No backlight string found\n"); + return -EINVAL; + } + + if (lmu_bl->mode == BL_PWM_BASED) + return lm3532_bl_select_pwm_bank(lmu_bl, bank_id); + + return 0; +} + +static int lm3532_bl_set_current_limit(struct ti_lmu_bl *lmu_bl) +{ + u8 reg[] = { LM3532_REG_IMAX_A, LM3532_REG_IMAX_B, LM3532_REG_IMAX_C }; + + return ti_lmu_write_byte(lmu_bl->chip->lmu, reg[lmu_bl->bank_id], + lmu_bl->imax); +} + +static int lm3532_bl_set_ramp(struct ti_lmu_bl *lmu_bl) +{ + int ret, index; + + index = ti_lmu_backlight_get_ramp_index(lmu_bl, BL_RAMP_UP); + if (index > 0) { + ret = ti_lmu_update_bits(lmu_bl->chip->lmu, LM3532_REG_RAMPUP, + LM3532_RAMPUP_MASK, + index << LM3532_RAMPUP_SHIFT); + if (ret) + return ret; + } + + index = ti_lmu_backlight_get_ramp_index(lmu_bl, BL_RAMP_DOWN); + if (index > 0) { + ret = ti_lmu_update_bits(lmu_bl->chip->lmu, LM3532_REG_RAMPDN, + LM3532_RAMPDN_MASK, + index << LM3532_RAMPDN_SHIFT); + if (ret) + return ret; + } + + return 0; +} + +static int lm3532_bl_configure(struct ti_lmu_bl *lmu_bl) +{ + int ret; + + ret = lm3532_bl_string_configure(lmu_bl); + if (ret) + return ret; + + ret = lm3532_bl_set_current_limit(lmu_bl); + if (ret) + return ret; + + return lm3532_bl_set_ramp(lmu_bl); +} + +/* Backlight ramp up/down time. Unit is msec. */ +static const int lm3532_ramp_table[] = { 0, 1, 2, 4, 8, 16, 32, 65 }; + +static const struct ti_lmu_bl_ops lm3532_lmu_ops = { + .init = lm3532_bl_init, + .configure = lm3532_bl_configure, + .update_brightness = lm3532_bl_set_brightness, + .bl_enable = lm3532_bl_enable, + .max_brightness = LM3532_MAX_BRIGHTNESS, + .ramp_table = lm3532_ramp_table, + .size_ramp = ARRAY_SIZE(lm3532_ramp_table), +}; + +/* LM3532 backlight of_device_id */ +TI_LMU_BL_OF_DEVICE(lm3532, "ti,lm3532-backlight"); + +/* LM3532 backlight platform driver */ +TI_LMU_BL_PLATFORM_DRIVER(lm3532, "lm3532-backlight"); + +MODULE_DESCRIPTION("TI LM3532 Backlight Driver"); +MODULE_AUTHOR("Milo Kim"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:lm3532-backlight"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/