Haavard Skinnemoen | 18f65c7 | 2007-09-02 23:15:49 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Power control for Samsung LTV350QV Quarter VGA LCD Panel |
| 3 | * |
| 4 | * Copyright (C) 2006, 2007 Atmel Corporation |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | #include <linux/delay.h> |
| 11 | #include <linux/err.h> |
| 12 | #include <linux/fb.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/lcd.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/spi/spi.h> |
| 17 | |
| 18 | #include "ltv350qv.h" |
| 19 | |
| 20 | #define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL) |
| 21 | |
| 22 | struct ltv350qv { |
| 23 | struct spi_device *spi; |
| 24 | u8 *buffer; |
| 25 | int power; |
| 26 | struct lcd_device *ld; |
| 27 | }; |
| 28 | |
| 29 | /* |
| 30 | * The power-on and power-off sequences are taken from the |
| 31 | * LTV350QV-F04 data sheet from Samsung. The register definitions are |
| 32 | * taken from the S6F2002 command list also from Samsung. Both |
| 33 | * documents are distributed with the AVR32 Linux BSP CD from Atmel. |
| 34 | * |
| 35 | * There's still some voodoo going on here, but it's a lot better than |
| 36 | * in the first incarnation of the driver where all we had was the raw |
| 37 | * numbers from the initialization sequence. |
| 38 | */ |
| 39 | static int ltv350qv_write_reg(struct ltv350qv *lcd, u8 reg, u16 val) |
| 40 | { |
| 41 | struct spi_message msg; |
| 42 | struct spi_transfer index_xfer = { |
| 43 | .len = 3, |
| 44 | .cs_change = 1, |
| 45 | }; |
| 46 | struct spi_transfer value_xfer = { |
| 47 | .len = 3, |
| 48 | }; |
| 49 | |
| 50 | spi_message_init(&msg); |
| 51 | |
| 52 | /* register index */ |
| 53 | lcd->buffer[0] = LTV_OPC_INDEX; |
| 54 | lcd->buffer[1] = 0x00; |
| 55 | lcd->buffer[2] = reg & 0x7f; |
| 56 | index_xfer.tx_buf = lcd->buffer; |
| 57 | spi_message_add_tail(&index_xfer, &msg); |
| 58 | |
| 59 | /* register value */ |
| 60 | lcd->buffer[4] = LTV_OPC_DATA; |
| 61 | lcd->buffer[5] = val >> 8; |
| 62 | lcd->buffer[6] = val; |
| 63 | value_xfer.tx_buf = lcd->buffer + 4; |
| 64 | spi_message_add_tail(&value_xfer, &msg); |
| 65 | |
| 66 | return spi_sync(lcd->spi, &msg); |
| 67 | } |
| 68 | |
| 69 | /* The comments are taken straight from the data sheet */ |
| 70 | static int ltv350qv_power_on(struct ltv350qv *lcd) |
| 71 | { |
| 72 | int ret; |
| 73 | |
| 74 | /* Power On Reset Display off State */ |
| 75 | if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, 0x0000)) |
| 76 | goto err; |
| 77 | msleep(15); |
| 78 | |
| 79 | /* Power Setting Function 1 */ |
| 80 | if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE)) |
| 81 | goto err; |
| 82 | if (ltv350qv_write_reg(lcd, LTV_PWRCTL2, LTV_VCOML_ENABLE)) |
| 83 | goto err_power1; |
| 84 | |
| 85 | /* Power Setting Function 2 */ |
| 86 | if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| 87 | LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5) |
| 88 | | LTV_SUPPLY_CURRENT(5))) |
| 89 | goto err_power2; |
| 90 | |
| 91 | msleep(55); |
| 92 | |
| 93 | /* Instruction Setting */ |
| 94 | ret = ltv350qv_write_reg(lcd, LTV_IFCTL, |
| 95 | LTV_NMD | LTV_REV | LTV_NL(0x1d)); |
| 96 | ret |= ltv350qv_write_reg(lcd, LTV_DATACTL, |
| 97 | LTV_DS_SAME | LTV_CHS_480 |
| 98 | | LTV_DF_RGB | LTV_RGB_BGR); |
| 99 | ret |= ltv350qv_write_reg(lcd, LTV_ENTRY_MODE, |
| 100 | LTV_VSPL_ACTIVE_LOW |
| 101 | | LTV_HSPL_ACTIVE_LOW |
| 102 | | LTV_DPL_SAMPLE_RISING |
| 103 | | LTV_EPL_ACTIVE_LOW |
| 104 | | LTV_SS_RIGHT_TO_LEFT); |
| 105 | ret |= ltv350qv_write_reg(lcd, LTV_GATECTL1, LTV_CLW(3)); |
| 106 | ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| 107 | LTV_NW_INV_1LINE | LTV_FWI(3)); |
| 108 | ret |= ltv350qv_write_reg(lcd, LTV_VBP, 0x000a); |
| 109 | ret |= ltv350qv_write_reg(lcd, LTV_HBP, 0x0021); |
| 110 | ret |= ltv350qv_write_reg(lcd, LTV_SOTCTL, LTV_SDT(3) | LTV_EQ(0)); |
| 111 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(0), 0x0103); |
| 112 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(1), 0x0301); |
| 113 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(2), 0x1f0f); |
| 114 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(3), 0x1f0f); |
| 115 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(4), 0x0707); |
| 116 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(5), 0x0307); |
| 117 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(6), 0x0707); |
| 118 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(7), 0x0000); |
| 119 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(8), 0x0004); |
| 120 | ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(9), 0x0000); |
| 121 | if (ret) |
| 122 | goto err_settings; |
| 123 | |
| 124 | /* Wait more than 2 frames */ |
| 125 | msleep(20); |
| 126 | |
| 127 | /* Display On Sequence */ |
| 128 | ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| 129 | LTV_VCOM_DISABLE | LTV_VCOMOUT_ENABLE |
| 130 | | LTV_POWER_ON | LTV_DRIVE_CURRENT(5) |
| 131 | | LTV_SUPPLY_CURRENT(5)); |
| 132 | ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| 133 | LTV_NW_INV_1LINE | LTV_DSC | LTV_FWI(3)); |
| 134 | if (ret) |
| 135 | goto err_disp_on; |
| 136 | |
| 137 | /* Display should now be ON. Phew. */ |
| 138 | return 0; |
| 139 | |
| 140 | err_disp_on: |
| 141 | /* |
| 142 | * Try to recover. Error handling probably isn't very useful |
| 143 | * at this point, just make a best effort to switch the panel |
| 144 | * off. |
| 145 | */ |
| 146 | ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| 147 | LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5) |
| 148 | | LTV_SUPPLY_CURRENT(5)); |
| 149 | ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| 150 | LTV_NW_INV_1LINE | LTV_FWI(3)); |
| 151 | err_settings: |
| 152 | err_power2: |
| 153 | err_power1: |
| 154 | ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000); |
| 155 | msleep(1); |
| 156 | err: |
| 157 | ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE); |
| 158 | return -EIO; |
| 159 | } |
| 160 | |
| 161 | static int ltv350qv_power_off(struct ltv350qv *lcd) |
| 162 | { |
| 163 | int ret; |
| 164 | |
| 165 | /* Display Off Sequence */ |
| 166 | ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1, |
| 167 | LTV_VCOM_DISABLE |
| 168 | | LTV_DRIVE_CURRENT(5) |
| 169 | | LTV_SUPPLY_CURRENT(5)); |
| 170 | ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2, |
| 171 | LTV_NW_INV_1LINE | LTV_FWI(3)); |
| 172 | |
| 173 | /* Power down setting 1 */ |
| 174 | ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000); |
| 175 | |
| 176 | /* Wait at least 1 ms */ |
| 177 | msleep(1); |
| 178 | |
| 179 | /* Power down setting 2 */ |
| 180 | ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE); |
| 181 | |
| 182 | /* |
| 183 | * No point in trying to recover here. If we can't switch the |
| 184 | * panel off, what are we supposed to do other than inform the |
| 185 | * user about the failure? |
| 186 | */ |
| 187 | if (ret) |
| 188 | return -EIO; |
| 189 | |
| 190 | /* Display power should now be OFF */ |
| 191 | return 0; |
| 192 | } |
| 193 | |
| 194 | static int ltv350qv_power(struct ltv350qv *lcd, int power) |
| 195 | { |
| 196 | int ret = 0; |
| 197 | |
| 198 | if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power)) |
| 199 | ret = ltv350qv_power_on(lcd); |
| 200 | else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power)) |
| 201 | ret = ltv350qv_power_off(lcd); |
| 202 | |
| 203 | if (!ret) |
| 204 | lcd->power = power; |
| 205 | |
| 206 | return ret; |
| 207 | } |
| 208 | |
| 209 | static int ltv350qv_set_power(struct lcd_device *ld, int power) |
| 210 | { |
| 211 | struct ltv350qv *lcd = lcd_get_data(ld); |
| 212 | |
| 213 | return ltv350qv_power(lcd, power); |
| 214 | } |
| 215 | |
| 216 | static int ltv350qv_get_power(struct lcd_device *ld) |
| 217 | { |
| 218 | struct ltv350qv *lcd = lcd_get_data(ld); |
| 219 | |
| 220 | return lcd->power; |
| 221 | } |
| 222 | |
| 223 | static struct lcd_ops ltv_ops = { |
| 224 | .get_power = ltv350qv_get_power, |
| 225 | .set_power = ltv350qv_set_power, |
| 226 | }; |
| 227 | |
| 228 | static int __devinit ltv350qv_probe(struct spi_device *spi) |
| 229 | { |
| 230 | struct ltv350qv *lcd; |
| 231 | struct lcd_device *ld; |
| 232 | int ret; |
| 233 | |
| 234 | lcd = kzalloc(sizeof(struct ltv350qv), GFP_KERNEL); |
| 235 | if (!lcd) |
| 236 | return -ENOMEM; |
| 237 | |
| 238 | lcd->spi = spi; |
| 239 | lcd->power = FB_BLANK_POWERDOWN; |
| 240 | lcd->buffer = kzalloc(8, GFP_KERNEL); |
| 241 | |
| 242 | ld = lcd_device_register("ltv350qv", &spi->dev, lcd, <v_ops); |
| 243 | if (IS_ERR(ld)) { |
| 244 | ret = PTR_ERR(ld); |
| 245 | goto out_free_lcd; |
| 246 | } |
| 247 | lcd->ld = ld; |
| 248 | |
| 249 | ret = ltv350qv_power(lcd, FB_BLANK_UNBLANK); |
| 250 | if (ret) |
| 251 | goto out_unregister; |
| 252 | |
| 253 | dev_set_drvdata(&spi->dev, lcd); |
| 254 | |
| 255 | return 0; |
| 256 | |
| 257 | out_unregister: |
| 258 | lcd_device_unregister(ld); |
| 259 | out_free_lcd: |
| 260 | kfree(lcd); |
| 261 | return ret; |
| 262 | } |
| 263 | |
| 264 | static int __devexit ltv350qv_remove(struct spi_device *spi) |
| 265 | { |
| 266 | struct ltv350qv *lcd = dev_get_drvdata(&spi->dev); |
| 267 | |
| 268 | ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| 269 | lcd_device_unregister(lcd->ld); |
| 270 | kfree(lcd); |
| 271 | |
| 272 | return 0; |
| 273 | } |
| 274 | |
| 275 | #ifdef CONFIG_PM |
| 276 | static int ltv350qv_suspend(struct spi_device *spi, pm_message_t state) |
| 277 | { |
| 278 | struct ltv350qv *lcd = dev_get_drvdata(&spi->dev); |
| 279 | |
| 280 | return ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| 281 | } |
| 282 | |
| 283 | static int ltv350qv_resume(struct spi_device *spi) |
| 284 | { |
| 285 | struct ltv350qv *lcd = dev_get_drvdata(&spi->dev); |
| 286 | |
| 287 | return ltv350qv_power(lcd, FB_BLANK_UNBLANK); |
| 288 | } |
| 289 | #else |
| 290 | #define ltv350qv_suspend NULL |
| 291 | #define ltv350qv_resume NULL |
| 292 | #endif |
| 293 | |
| 294 | /* Power down all displays on reboot, poweroff or halt */ |
| 295 | static void ltv350qv_shutdown(struct spi_device *spi) |
| 296 | { |
| 297 | struct ltv350qv *lcd = dev_get_drvdata(&spi->dev); |
| 298 | |
| 299 | ltv350qv_power(lcd, FB_BLANK_POWERDOWN); |
| 300 | } |
| 301 | |
| 302 | static struct spi_driver ltv350qv_driver = { |
| 303 | .driver = { |
| 304 | .name = "ltv350qv", |
| 305 | .bus = &spi_bus_type, |
| 306 | .owner = THIS_MODULE, |
| 307 | }, |
| 308 | |
| 309 | .probe = ltv350qv_probe, |
| 310 | .remove = __devexit_p(ltv350qv_remove), |
| 311 | .shutdown = ltv350qv_shutdown, |
| 312 | .suspend = ltv350qv_suspend, |
| 313 | .resume = ltv350qv_resume, |
| 314 | }; |
| 315 | |
| 316 | static int __init ltv350qv_init(void) |
| 317 | { |
| 318 | return spi_register_driver(<v350qv_driver); |
| 319 | } |
| 320 | |
| 321 | static void __exit ltv350qv_exit(void) |
| 322 | { |
| 323 | spi_unregister_driver(<v350qv_driver); |
| 324 | } |
| 325 | module_init(ltv350qv_init); |
| 326 | module_exit(ltv350qv_exit); |
| 327 | |
| 328 | MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>"); |
| 329 | MODULE_DESCRIPTION("Samsung LTV350QV LCD Driver"); |
| 330 | MODULE_LICENSE("GPL"); |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 331 | MODULE_ALIAS("spi:ltv350qv"); |