diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-12-15 14:52:16 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-12-15 14:52:16 -0300 |
commit | 8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch) | |
tree | e9891aa6c295060d065adffd610c4f49ecf884f3 /drivers/staging/fbtft/fb_uc1611.c | |
parent | a71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff) |
Linux-libre 4.3.2-gnu
Diffstat (limited to 'drivers/staging/fbtft/fb_uc1611.c')
-rw-r--r-- | drivers/staging/fbtft/fb_uc1611.c | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/drivers/staging/fbtft/fb_uc1611.c b/drivers/staging/fbtft/fb_uc1611.c new file mode 100644 index 000000000..5cafa50d1 --- /dev/null +++ b/drivers/staging/fbtft/fb_uc1611.c @@ -0,0 +1,350 @@ +/* + * FB driver for the UltraChip UC1611 LCD controller + * + * The display is 4-bit grayscale (16 shades) 240x160. + * + * Copyright (C) 2015 Henri Chain + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/gpio.h> +#include <linux/spi/spi.h> +#include <linux/delay.h> + +#include "fbtft.h" + +#define DRVNAME "fb_uc1611" +#define WIDTH 240 +#define HEIGHT 160 +#define BPP 8 +#define FPS 40 + +/* + * LCD voltage is a combination of ratio, gain, pot and temp + * + * V_LCD = V_BIAS * ratio + * V_LCD = (C_V0 + C_PM × pot) * (1 + (T - 25) * temp) + * C_V0 and C_PM depend on ratio and gain + * T is ambient temperature + */ + +/* BR -> actual ratio: 0-3 -> 5, 10, 11, 13 */ +static unsigned ratio = 2; +module_param(ratio, uint, 0); +MODULE_PARM_DESC(ratio, "BR[1:0] Bias voltage ratio: 0-3 (default: 2)"); + +static unsigned gain = 3; +module_param(gain, uint, 0); +MODULE_PARM_DESC(gain, "GN[1:0] Bias voltage gain: 0-3 (default: 3)"); + +static unsigned pot = 16; +module_param(pot, uint, 0); +MODULE_PARM_DESC(pot, "PM[6:0] Bias voltage pot.: 0-63 (default: 16)"); + +/* TC -> % compensation per deg C: 0-3 -> -.05, -.10, -.015, -.20 */ +static unsigned temp; +module_param(temp, uint, 0); +MODULE_PARM_DESC(temp, "TC[1:0] Temperature compensation: 0-3 (default: 0)"); + +/* PC[1:0] -> LCD capacitance: 0-3 -> <20nF, 20-28 nF, 29-40 nF, 40-56 nF */ +static unsigned load = 1; +module_param(load, uint, 0); +MODULE_PARM_DESC(load, "PC[1:0] Panel Loading: 0-3 (default: 1)"); + +/* PC[3:2] -> V_LCD: 0, 1, 3 -> ext., int. with ratio = 5, int. standard */ +static unsigned pump = 3; +module_param(pump, uint, 0); +MODULE_PARM_DESC(pump, "PC[3:2] Pump control: 0,1,3 (default: 3)"); + +static int init_display(struct fbtft_par *par) +{ + int ret; + + fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); + + /* Set CS active high */ + par->spi->mode |= SPI_CS_HIGH; + ret = spi_setup(par->spi); + if (ret) { + dev_err(par->info->device, "Could not set SPI_CS_HIGH\n"); + return ret; + } + + /* Reset controller */ + write_reg(par, 0xE2); + + /* Set bias ratio */ + write_reg(par, 0xE8 | (ratio & 0x03)); + + /* Set bias gain and potentiometer */ + write_reg(par, 0x81); + write_reg(par, (gain & 0x03) << 6 | (pot & 0x3F)); + + /* Set temperature compensation */ + write_reg(par, 0x24 | (temp & 0x03)); + + /* Set panel loading */ + write_reg(par, 0x28 | (load & 0x03)); + + /* Set pump control */ + write_reg(par, 0x2C | (pump & 0x03)); + + /* Set inverse display */ + write_reg(par, 0xA6 | (0x01 & 0x01)); + + /* Set 4-bit grayscale mode */ + write_reg(par, 0xD0 | (0x02 & 0x03)); + + /* Set Display enable */ + write_reg(par, 0xA8 | 0x07); + + return 0; +} + +static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) +{ + fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par, + "%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", + __func__, xs, ys, xe, ye); + + switch (par->info->var.rotate) { + case 90: + case 270: + /* Set column address */ + write_reg(par, ys & 0x0F); + write_reg(par, 0x10 | (ys >> 4)); + + /* Set page address (divide xs by 2) (not used by driver) */ + write_reg(par, 0x60 | ((xs >> 1) & 0x0F)); + write_reg(par, 0x70 | (xs >> 5)); + break; + default: + /* Set column address (not used by driver) */ + write_reg(par, xs & 0x0F); + write_reg(par, 0x10 | (xs >> 4)); + + /* Set page address (divide ys by 2) */ + write_reg(par, 0x60 | ((ys >> 1) & 0x0F)); + write_reg(par, 0x70 | (ys >> 5)); + break; + } +} + +static int blank(struct fbtft_par *par, bool on) +{ + fbtft_par_dbg(DEBUG_BLANK, par, "%s(blank=%s)\n", + __func__, on ? "true" : "false"); + + if (on) + write_reg(par, 0xA8 | 0x00); + else + write_reg(par, 0xA8 | 0x07); + return 0; +} + +static int set_var(struct fbtft_par *par) +{ + fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); + + /* par->info->fix.visual = FB_VISUAL_PSEUDOCOLOR; */ + par->info->var.grayscale = 1; + par->info->var.red.offset = 0; + par->info->var.red.length = 8; + par->info->var.green.offset = 0; + par->info->var.green.length = 8; + par->info->var.blue.offset = 0; + par->info->var.blue.length = 8; + par->info->var.transp.offset = 0; + par->info->var.transp.length = 0; + + switch (par->info->var.rotate) { + case 90: + /* Set RAM address control */ + write_reg(par, 0x88 + | (0x0 & 0x1) << 2 /* Increment positively */ + | (0x1 & 0x1) << 1 /* Increment page first */ + | (0x1 & 0x1)); /* Wrap around (default) */ + + /* Set LCD mapping */ + write_reg(par, 0xC0 + | (0x0 & 0x1) << 2 /* Mirror Y OFF */ + | (0x0 & 0x1) << 1 /* Mirror X OFF */ + | (0x0 & 0x1)); /* MS nibble last (default) */ + break; + case 180: + /* Set RAM address control */ + write_reg(par, 0x88 + | (0x0 & 0x1) << 2 /* Increment positively */ + | (0x0 & 0x1) << 1 /* Increment column first */ + | (0x1 & 0x1)); /* Wrap around (default) */ + + /* Set LCD mapping */ + write_reg(par, 0xC0 + | (0x1 & 0x1) << 2 /* Mirror Y ON */ + | (0x0 & 0x1) << 1 /* Mirror X OFF */ + | (0x0 & 0x1)); /* MS nibble last (default) */ + break; + case 270: + /* Set RAM address control */ + write_reg(par, 0x88 + | (0x0 & 0x1) << 2 /* Increment positively */ + | (0x1 & 0x1) << 1 /* Increment page first */ + | (0x1 & 0x1)); /* Wrap around (default) */ + + /* Set LCD mapping */ + write_reg(par, 0xC0 + | (0x1 & 0x1) << 2 /* Mirror Y ON */ + | (0x1 & 0x1) << 1 /* Mirror X ON */ + | (0x0 & 0x1)); /* MS nibble last (default) */ + break; + default: + /* Set RAM address control */ + write_reg(par, 0x88 + | (0x0 & 0x1) << 2 /* Increment positively */ + | (0x0 & 0x1) << 1 /* Increment column first */ + | (0x1 & 0x1)); /* Wrap around (default) */ + + /* Set LCD mapping */ + write_reg(par, 0xC0 + | (0x0 & 0x1) << 2 /* Mirror Y OFF */ + | (0x1 & 0x1) << 1 /* Mirror X ON */ + | (0x0 & 0x1)); /* MS nibble last (default) */ + break; + } + + return 0; +} + +static int write_vmem(struct fbtft_par *par, size_t offset, size_t len) +{ + u8 *vmem8 = (u8 *)(par->info->screen_base); + u8 *buf8 = (u8 *)(par->txbuf.buf); + u16 *buf16 = (u16 *)(par->txbuf.buf); + int line_length = par->info->fix.line_length; + int y_start = (offset / line_length); + int y_end = (offset + len - 1) / line_length; + int x, y, i; + int ret = 0; + + fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s()\n", __func__); + + switch (par->pdata->display.buswidth) { + case 8: + switch (par->info->var.rotate) { + case 90: + case 270: + i = y_start * line_length; + for (y = y_start; y <= y_end; y++) { + for (x = 0; x < line_length; x += 2) { + *buf8 = vmem8[i] >> 4; + *buf8 |= vmem8[i + 1] & 0xF0; + buf8++; + i += 2; + } + } + break; + default: + /* Must be even because pages are two lines */ + y_start &= 0xFE; + i = y_start * line_length; + for (y = y_start; y <= y_end; y += 2) { + for (x = 0; x < line_length; x++) { + *buf8 = vmem8[i] >> 4; + *buf8 |= vmem8[i + line_length] & 0xF0; + buf8++; + i++; + } + i += line_length; + } + break; + } + gpio_set_value(par->gpio.dc, 1); + + /* Write data */ + ret = par->fbtftops.write(par, par->txbuf.buf, len / 2); + break; + case 9: + switch (par->info->var.rotate) { + case 90: + case 270: + i = y_start * line_length; + for (y = y_start; y <= y_end; y++) { + for (x = 0; x < line_length; x += 2) { + *buf16 = 0x100; + *buf16 |= vmem8[i] >> 4; + *buf16 |= vmem8[i + 1] & 0xF0; + buf16++; + i += 2; + } + } + break; + default: + /* Must be even because pages are two lines */ + y_start &= 0xFE; + i = y_start * line_length; + for (y = y_start; y <= y_end; y += 2) { + for (x = 0; x < line_length; x++) { + *buf16 = 0x100; + *buf16 |= vmem8[i] >> 4; + *buf16 |= vmem8[i + line_length] & 0xF0; + buf16++; + i++; + } + i += line_length; + } + break; + } + + /* Write data */ + ret = par->fbtftops.write(par, par->txbuf.buf, len); + break; + default: + dev_err(par->info->device, "unsupported buswidth %d\n", + par->pdata->display.buswidth); + } + + if (ret < 0) + dev_err(par->info->device, "write failed and returned: %d\n", + ret); + + return ret; +} + +static struct fbtft_display display = { + .txbuflen = -1, + .regwidth = 8, + .width = WIDTH, + .height = HEIGHT, + .bpp = BPP, + .fps = FPS, + .fbtftops = { + .write_vmem = write_vmem, + .init_display = init_display, + .set_addr_win = set_addr_win, + .set_var = set_var, + .blank = blank, + }, +}; + +FBTFT_REGISTER_DRIVER(DRVNAME, "ultrachip,uc1611", &display); + +MODULE_ALIAS("spi:" DRVNAME); +MODULE_ALIAS("platform:" DRVNAME); +MODULE_ALIAS("spi:uc1611"); +MODULE_ALIAS("platform:uc1611"); + +MODULE_DESCRIPTION("FB driver for the UC1611 LCD controller"); +MODULE_AUTHOR("Henri Chain"); +MODULE_LICENSE("GPL"); |