| /* |
| * Power control for Samsung LTV350QV Quarter VGA LCD Panel |
| * |
| * Copyright (C) 2006, 2007 Atmel Corporation |
| * |
| * 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 <linux/delay.h> |
| #include <linux/err.h> |
| #include <linux/fb.h> |
| #include <linux/init.h> |
| #include <linux/lcd.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/spi/spi.h> |
| |
| #include "ltv350qv.h" |
| |
| #define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL) |
| |
| struct ltv350qv { |
| struct spi_device *spi; |
| u8 *buffer; |
| int power; |
| struct lcd_device *ld; |
| }; |
| |
| /* |
| * The power-on and power-off sequences are taken from the |
| * LTV350QV-F04 data sheet from Samsung. The register definitions are |
| * taken from the S6F2002 command list also from Samsung. Both |
| * documents are distributed with the AVR32 Linux BSP CD from Atmel. |
| * |
| * There's still some voodoo going on here, but it's a lot better than |
| * in the first incarnation of the driver where all we had was the raw |
| * numbers from the initialization sequence. |
| */ |
| static int ltv350qv_write_reg(struct ltv350qv *lcd, u8 reg, u16 val) |
| { |
| struct spi_message msg; |
| struct spi_transfer index_xfer = { |
| .len = 3, |
| .cs_change = 1, |
| }; |
| struct spi_transfer value_xfer = { |
| .len = 3, |
| }; |
| |
| spi_message_init(&msg); |
| |
| /* register index */ |
| lcd->buffer[0] = LTV_OPC_INDEX; |
| lcd->buffer[1] = 0x00; |
| lcd->buffer[2] = reg & 0x7f; |
| index_xfer.tx_buf = lcd->buffer; |
| spi_message_add_tail(&index_xfer, &msg); |
| |
| /* register value */ |
| lcd->buffer[4] = LTV_OPC_DATA; |
| lcd->buffer[5] = val >> 8; |
| lcd->buffer[6] = val; |
| value_xfer.tx_buf = lcd->buffer + 4; |
| spi_message_add_tail(&value_xfer, &msg); |
| |
| return spi_sync(lcd->spi, &msg); |
| } |
| |
| /* The comments are taken straight from the data sheet */ |
| static int ltv350qv_power_on(struct ltv350qv *lcd) |
| { |
| int ret; |
| |
| /* Power On Reset Display off State */ |
| if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, 0x0000)) |
| goto err; |
| usleep_range(15000, 16000); |
| |
| /* Power Setting Function 1 */ |
| if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE)) |
| goto err; |
| if (ltv350qv_write_reg(lcd, LTV_PWRCTL2, LTV_VCOML_ENABLE)) |
| goto err_power1; |
| |
| /* Power Setting Function 2 */ |
| if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5) |
| | LTV_SUPPLY_CURRENT(5))) |
| goto err_power2; |
| |
| msleep(55); |
| |
| /* Instruction Setting */ |
| ret = ltv350qv_write_reg(lcd, LTV_IFCTL, |
| LTV_NMD | LTV_REV | LTV_NL(0x1d)); |
| ret |= ltv350qv_write_reg(lcd, LTV_DATACTL, |
| LTV_DS_SAME | LTV_CHS_480 |
| | LTV_DF_RGB | LTV_RGB_BGR); |
| ret |= ltv350qv_write_reg(lcd, LTV_ENTRY_MODE, |
| LTV_VSPL_ACTIVE_LOW |
| | LTV_HSPL_ACTIVE_LOW |
| | LTV_DPL_SAMPLE_RISING |
| | LTV_EPL_ACTIVE_LOW |
| | LTV_SS_RIGHT_TO_LEFT); |
| ret |= ltv350qv_write_reg(lcd, LTV_GATECTL1, LTV_CLW(3)); |
| ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| LTV_NW_INV_1LINE | LTV_FWI(3)); |
| ret |= ltv350qv_write_reg(lcd, LTV_VBP, 0x000a); |
| ret |= ltv350qv_write_reg(lcd, LTV_HBP, 0x0021); |
| ret |= ltv350qv_write_reg(lcd, LTV_SOTCTL, LTV_SDT(3) | LTV_EQ(0)); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(0), 0x0103); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(1), 0x0301); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(2), 0x1f0f); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(3), 0x1f0f); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(4), 0x0707); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(5), 0x0307); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(6), 0x0707); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(7), 0x0000); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(8), 0x0004); |
| ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(9), 0x0000); |
| if (ret) |
| goto err_settings; |
| |
| /* Wait more than 2 frames */ |
| msleep(20); |
| |
| /* Display On Sequence */ |
| ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| LTV_VCOM_DISABLE | LTV_VCOMOUT_ENABLE |
| | LTV_POWER_ON | LTV_DRIVE_CURRENT(5) |
| | LTV_SUPPLY_CURRENT(5)); |
| ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| LTV_NW_INV_1LINE | LTV_DSC | LTV_FWI(3)); |
| if (ret) |
| goto err_disp_on; |
| |
| /* Display should now be ON. Phew. */ |
| return 0; |
| |
| err_disp_on: |
| /* |
| * Try to recover. Error handling probably isn't very useful |
| * at this point, just make a best effort to switch the panel |
| * off. |
| */ |
| ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5) |
| | LTV_SUPPLY_CURRENT(5)); |
| ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| LTV_NW_INV_1LINE | LTV_FWI(3)); |
| err_settings: |
| err_power2: |
| err_power1: |
| ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000); |
| usleep_range(1000, 1100); |
| err: |
| ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE); |
| return -EIO; |
| } |
| |
| static int ltv350qv_power_off(struct ltv350qv *lcd) |
| { |
| int ret; |
| |
| /* Display Off Sequence */ |
| ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| LTV_VCOM_DISABLE |
| | LTV_DRIVE_CURRENT(5) |
| | LTV_SUPPLY_CURRENT(5)); |
| ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| LTV_NW_INV_1LINE | LTV_FWI(3)); |
| |
| /* Power down setting 1 */ |
| ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000); |
| |
| /* Wait at least 1 ms */ |
| usleep_range(1000, 1100); |
| |
| /* Power down setting 2 */ |
| ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE); |
| |
| /* |
| * No point in trying to recover here. If we can't switch the |
| * panel off, what are we supposed to do other than inform the |
| * user about the failure? |
| */ |
| if (ret) |
| return -EIO; |
| |
| /* Display power should now be OFF */ |
| return 0; |
| } |
| |
| static int ltv350qv_power(struct ltv350qv *lcd, int power) |
| { |
| int ret = 0; |
| |
| if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power)) |
| ret = ltv350qv_power_on(lcd); |
| else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power)) |
| ret = ltv350qv_power_off(lcd); |
| |
| if (!ret) |
| lcd->power = power; |
| |
| return ret; |
| } |
| |
| static int ltv350qv_set_power(struct lcd_device *ld, int power) |
| { |
| struct ltv350qv *lcd = lcd_get_data(ld); |
| |
| return ltv350qv_power(lcd, power); |
| } |
| |
| static int ltv350qv_get_power(struct lcd_device *ld) |
| { |
| struct ltv350qv *lcd = lcd_get_data(ld); |
| |
| return lcd->power; |
| } |
| |
| static struct lcd_ops ltv_ops = { |
| .get_power = ltv350qv_get_power, |
| .set_power = ltv350qv_set_power, |
| }; |
| |
| static int ltv350qv_probe(struct spi_device *spi) |
| { |
| struct ltv350qv *lcd; |
| struct lcd_device *ld; |
| int ret; |
| |
| lcd = devm_kzalloc(&spi->dev, sizeof(struct ltv350qv), GFP_KERNEL); |
| if (!lcd) |
| return -ENOMEM; |
| |
| lcd->spi = spi; |
| lcd->power = FB_BLANK_POWERDOWN; |
| lcd->buffer = devm_kzalloc(&spi->dev, 8, GFP_KERNEL); |
| if (!lcd->buffer) |
| return -ENOMEM; |
| |
| ld = lcd_device_register("ltv350qv", &spi->dev, lcd, <v_ops); |
| if (IS_ERR(ld)) |
| return PTR_ERR(ld); |
| |
| lcd->ld = ld; |
| |
| ret = ltv350qv_power(lcd, FB_BLANK_UNBLANK); |
| if (ret) |
| goto out_unregister; |
| |
| spi_set_drvdata(spi, lcd); |
| |
| return 0; |
| |
| out_unregister: |
| lcd_device_unregister(ld); |
| return ret; |
| } |
| |
| static int ltv350qv_remove(struct spi_device *spi) |
| { |
| struct ltv350qv *lcd = spi_get_drvdata(spi); |
| |
| ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| lcd_device_unregister(lcd->ld); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int ltv350qv_suspend(struct device *dev) |
| { |
| struct ltv350qv *lcd = dev_get_drvdata(dev); |
| |
| return ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| } |
| |
| static int ltv350qv_resume(struct device *dev) |
| { |
| struct ltv350qv *lcd = dev_get_drvdata(dev); |
| |
| return ltv350qv_power(lcd, FB_BLANK_UNBLANK); |
| } |
| #endif |
| |
| static SIMPLE_DEV_PM_OPS(ltv350qv_pm_ops, ltv350qv_suspend, ltv350qv_resume); |
| |
| /* Power down all displays on reboot, poweroff or halt */ |
| static void ltv350qv_shutdown(struct spi_device *spi) |
| { |
| struct ltv350qv *lcd = spi_get_drvdata(spi); |
| |
| ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| } |
| |
| static struct spi_driver ltv350qv_driver = { |
| .driver = { |
| .name = "ltv350qv", |
| .owner = THIS_MODULE, |
| .pm = <v350qv_pm_ops, |
| }, |
| |
| .probe = ltv350qv_probe, |
| .remove = ltv350qv_remove, |
| .shutdown = ltv350qv_shutdown, |
| }; |
| |
| module_spi_driver(ltv350qv_driver); |
| |
| MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); |
| MODULE_DESCRIPTION("Samsung LTV350QV LCD Driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("spi:ltv350qv"); |