Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 1 | /* |
| 2 | * FB driver for the PCD8544 LCD Controller |
| 3 | * |
| 4 | * The display is monochrome and the video memory is RGB565. |
| 5 | * Any pixel value except 0 turns the pixel on. |
| 6 | * |
| 7 | * Copyright (C) 2013 Noralf Tronnes |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License as published by |
| 11 | * the Free Software Foundation; either version 2 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with this program; if not, write to the Free Software |
| 21 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 22 | */ |
| 23 | |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/kernel.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <linux/gpio.h> |
| 28 | #include <linux/spi/spi.h> |
| 29 | #include <linux/delay.h> |
| 30 | |
| 31 | #include "fbtft.h" |
| 32 | |
| 33 | #define DRVNAME "fb_pcd8544" |
| 34 | #define WIDTH 84 |
| 35 | #define HEIGHT 48 |
Heba Aamer | 8ccf155 | 2015-01-27 22:39:56 +0200 | [diff] [blame] | 36 | #define TXBUFLEN (84*6) |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 37 | #define DEFAULT_GAMMA "40" /* gamma controls the contrast in this driver */ |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 38 | |
Heba Aamer | 9b37a8a | 2015-01-27 22:42:59 +0200 | [diff] [blame] | 39 | static unsigned tc; |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 40 | module_param(tc, uint, 0); |
| 41 | MODULE_PARM_DESC(tc, "TC[1:0] Temperature coefficient: 0-3 (default: 0)"); |
| 42 | |
| 43 | static unsigned bs = 4; |
| 44 | module_param(bs, uint, 0); |
| 45 | MODULE_PARM_DESC(bs, "BS[2:0] Bias voltage level: 0-7 (default: 4)"); |
| 46 | |
| 47 | |
| 48 | static int init_display(struct fbtft_par *par) |
| 49 | { |
| 50 | fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); |
| 51 | |
| 52 | par->fbtftops.reset(par); |
| 53 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 54 | /* Function set |
| 55 | * |
| 56 | * 5:1 1 |
| 57 | * 2:0 PD - Powerdown control: chip is active |
| 58 | * 1:0 V - Entry mode: horizontal addressing |
| 59 | * 0:1 H - Extended instruction set control: extended |
| 60 | */ |
| 61 | write_reg(par, 0x21); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 62 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 63 | /* H=1 Temperature control |
| 64 | * |
| 65 | * 2:1 1 |
| 66 | * 1:x TC1 - Temperature Coefficient: 0x10 |
| 67 | * 0:x TC0 |
| 68 | */ |
| 69 | write_reg(par, 0x04 | (tc & 0x3)); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 70 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 71 | /* H=1 Bias system |
| 72 | * |
| 73 | * 4:1 1 |
| 74 | * 3:0 0 |
| 75 | * 2:x BS2 - Bias System |
| 76 | * 1:x BS1 |
| 77 | * 0:x BS0 |
| 78 | */ |
| 79 | write_reg(par, 0x10 | (bs & 0x7)); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 80 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 81 | /* Function set |
| 82 | * |
| 83 | * 5:1 1 |
| 84 | * 2:0 PD - Powerdown control: chip is active |
| 85 | * 1:1 V - Entry mode: vertical addressing |
| 86 | * 0:0 H - Extended instruction set control: basic |
| 87 | */ |
| 88 | write_reg(par, 0x22); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 89 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 90 | /* H=0 Display control |
| 91 | * |
| 92 | * 3:1 1 |
| 93 | * 2:1 D - DE: 10=normal mode |
| 94 | * 1:0 0 |
| 95 | * 0:0 E |
| 96 | */ |
| 97 | write_reg(par, 0x08 | 4); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) |
| 103 | { |
Cláudio Maia | 14cf23b | 2015-03-20 16:31:45 +0000 | [diff] [blame] | 104 | fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par, "%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", |
| 105 | __func__, xs, ys, xe, ye); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 106 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 107 | /* H=0 Set X address of RAM |
| 108 | * |
| 109 | * 7:1 1 |
| 110 | * 6-0: X[6:0] - 0x00 |
| 111 | */ |
| 112 | write_reg(par, 0x80); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 113 | |
Cláudio Maia | 4178549 | 2015-03-20 16:31:46 +0000 | [diff] [blame] | 114 | /* H=0 Set Y address of RAM |
| 115 | * |
| 116 | * 7:0 0 |
| 117 | * 6:1 1 |
| 118 | * 2-0: Y[2:0] - 0x0 |
| 119 | */ |
| 120 | write_reg(par, 0x40); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 121 | } |
| 122 | |
| 123 | static int write_vmem(struct fbtft_par *par, size_t offset, size_t len) |
| 124 | { |
| 125 | u16 *vmem16 = (u16 *)par->info->screen_base; |
| 126 | u8 *buf = par->txbuf.buf; |
| 127 | int x, y, i; |
| 128 | int ret = 0; |
| 129 | |
| 130 | fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "%s()\n", __func__); |
| 131 | |
Heba Aamer | e82fb2b | 2015-01-27 22:37:24 +0200 | [diff] [blame] | 132 | for (x = 0; x < 84; x++) { |
| 133 | for (y = 0; y < 6; y++) { |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 134 | *buf = 0x00; |
Aya Mahfouz | 9d1d0a3 | 2015-02-19 04:53:59 +0200 | [diff] [blame] | 135 | for (i = 0; i < 8; i++) |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 136 | *buf |= (vmem16[(y*8+i)*84+x] ? 1 : 0) << i; |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 137 | buf++; |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | /* Write data */ |
| 142 | gpio_set_value(par->gpio.dc, 1); |
| 143 | ret = par->fbtftops.write(par, par->txbuf.buf, 6*84); |
| 144 | if (ret < 0) |
Haneen Mohammed | aed1c72 | 2015-03-06 21:59:04 +0300 | [diff] [blame] | 145 | dev_err(par->info->device, "write failed and returned: %d\n", |
| 146 | ret); |
Thomas Petazzoni | 39c3907 | 2014-12-31 10:11:21 +0100 | [diff] [blame] | 147 | |
| 148 | return ret; |
| 149 | } |
| 150 | |
| 151 | static int set_gamma(struct fbtft_par *par, unsigned long *curves) |
| 152 | { |
| 153 | fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); |
| 154 | |
| 155 | /* apply mask */ |
| 156 | curves[0] &= 0x7F; |
| 157 | |
| 158 | write_reg(par, 0x23); /* turn on extended instruction set */ |
| 159 | write_reg(par, 0x80 | curves[0]); |
| 160 | write_reg(par, 0x22); /* turn off extended instruction set */ |
| 161 | |
| 162 | return 0; |
| 163 | } |
| 164 | |
| 165 | |
| 166 | static struct fbtft_display display = { |
| 167 | .regwidth = 8, |
| 168 | .width = WIDTH, |
| 169 | .height = HEIGHT, |
| 170 | .txbuflen = TXBUFLEN, |
| 171 | .gamma_num = 1, |
| 172 | .gamma_len = 1, |
| 173 | .gamma = DEFAULT_GAMMA, |
| 174 | .fbtftops = { |
| 175 | .init_display = init_display, |
| 176 | .set_addr_win = set_addr_win, |
| 177 | .write_vmem = write_vmem, |
| 178 | .set_gamma = set_gamma, |
| 179 | }, |
| 180 | .backlight = 1, |
| 181 | }; |
| 182 | FBTFT_REGISTER_DRIVER(DRVNAME, "philips,pdc8544", &display); |
| 183 | |
| 184 | MODULE_ALIAS("spi:" DRVNAME); |
| 185 | MODULE_ALIAS("spi:pdc8544"); |
| 186 | |
| 187 | MODULE_DESCRIPTION("FB driver for the PCD8544 LCD Controller"); |
| 188 | MODULE_AUTHOR("Noralf Tronnes"); |
| 189 | MODULE_LICENSE("GPL"); |