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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/staging/fbtft/fb_tls8204.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/staging/fbtft/fb_tls8204.c')
-rw-r--r--drivers/staging/fbtft/fb_tls8204.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/staging/fbtft/fb_tls8204.c b/drivers/staging/fbtft/fb_tls8204.c
new file mode 100644
index 000000000..bec6dd0ff
--- /dev/null
+++ b/drivers/staging/fbtft/fb_tls8204.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * FB driver for the TLS8204 LCD Controller
+ *
+ * The display is monochrome and the video memory is RGB565.
+ * Any pixel value except 0 turns the pixel on.
+ *
+ * Copyright (C) 2013 Noralf Tronnes
+ * Copyright (C) 2014 Michael Hope (adapted for the TLS8204)
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/gpio/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+
+#include "fbtft.h"
+
+#define DRVNAME "fb_tls8204"
+#define WIDTH 84
+#define HEIGHT 48
+#define TXBUFLEN WIDTH
+
+/* gamma is used to control contrast in this driver */
+#define DEFAULT_GAMMA "40"
+
+static unsigned int bs = 4;
+module_param(bs, uint, 0000);
+MODULE_PARM_DESC(bs, "BS[2:0] Bias voltage level: 0-7 (default: 4)");
+
+static int init_display(struct fbtft_par *par)
+{
+ par->fbtftops.reset(par);
+
+ /* Enter extended command mode */
+ write_reg(par, 0x21); /* 5:1 1
+ * 2:0 PD - Powerdown control: chip is active
+ * 1:0 V - Entry mode: horizontal addressing
+ * 0:1 H - Extended instruction set control:
+ * extended
+ */
+
+ /* H=1 Bias system */
+ write_reg(par, 0x10 | (bs & 0x7));
+ /* 4:1 1
+ * 3:0 0
+ * 2:x BS2 - Bias System
+ * 1:x BS1
+ * 0:x BS0
+ */
+
+ /* Set the address of the first display line. */
+ write_reg(par, 0x04 | (64 >> 6));
+ write_reg(par, 0x40 | (64 & 0x3F));
+
+ /* Enter H=0 standard command mode */
+ write_reg(par, 0x20);
+
+ /* H=0 Display control */
+ write_reg(par, 0x08 | 4);
+ /* 3:1 1
+ * 2:1 D - DE: 10=normal mode
+ * 1:0 0
+ * 0:0 E
+ */
+
+ return 0;
+}
+
+static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
+{
+ /* H=0 Set X address of RAM */
+ write_reg(par, 0x80); /* 7:1 1
+ * 6-0: X[6:0] - 0x00
+ */
+
+ /* H=0 Set Y address of RAM */
+ write_reg(par, 0x40); /* 7:0 0
+ * 6:1 1
+ * 2-0: Y[2:0] - 0x0
+ */
+}
+
+static int write_vmem(struct fbtft_par *par, size_t offset, size_t len)
+{
+ u16 *vmem16 = (u16 *)par->info->screen_buffer;
+ int x, y, i;
+ int ret = 0;
+
+ for (y = 0; y < HEIGHT / 8; y++) {
+ u8 *buf = par->txbuf.buf;
+ /* The display is 102x68 but the LCD is 84x48.
+ * Set the write pointer at the start of each row.
+ */
+ gpiod_set_value(par->gpio.dc, 0);
+ write_reg(par, 0x80 | 0);
+ write_reg(par, 0x40 | y);
+
+ for (x = 0; x < WIDTH; x++) {
+ u8 ch = 0;
+
+ for (i = 0; i < 8 * WIDTH; i += WIDTH) {
+ ch >>= 1;
+ if (vmem16[(y * 8 * WIDTH) + i + x])
+ ch |= 0x80;
+ }
+ *buf++ = ch;
+ }
+ /* Write the row */
+ gpiod_set_value(par->gpio.dc, 1);
+ ret = par->fbtftops.write(par, par->txbuf.buf, WIDTH);
+ if (ret < 0) {
+ dev_err(par->info->device,
+ "write failed and returned: %d\n", ret);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int set_gamma(struct fbtft_par *par, u32 *curves)
+{
+ /* apply mask */
+ curves[0] &= 0x7F;
+
+ write_reg(par, 0x21); /* turn on extended instruction set */
+ write_reg(par, 0x80 | curves[0]);
+ write_reg(par, 0x20); /* turn off extended instruction set */
+
+ return 0;
+}
+
+static struct fbtft_display display = {
+ .regwidth = 8,
+ .width = WIDTH,
+ .height = HEIGHT,
+ .txbuflen = TXBUFLEN,
+ .gamma_num = 1,
+ .gamma_len = 1,
+ .gamma = DEFAULT_GAMMA,
+ .fbtftops = {
+ .init_display = init_display,
+ .set_addr_win = set_addr_win,
+ .write_vmem = write_vmem,
+ .set_gamma = set_gamma,
+ },
+ .backlight = 1,
+};
+
+FBTFT_REGISTER_DRIVER(DRVNAME, "teralane,tls8204", &display);
+
+MODULE_ALIAS("spi:" DRVNAME);
+MODULE_ALIAS("spi:tls8204");
+
+MODULE_DESCRIPTION("FB driver for the TLS8204 LCD Controller");
+MODULE_AUTHOR("Michael Hope");
+MODULE_LICENSE("GPL");