linux/drivers/video/backlight/tdo24m.c
Robert Jarzmik 2023b0524a backlight: tdo24m: Fix the SPI CS between transfers
Currently the LCD display (TD035S) on the cm-x300 platform is broken and
remains blank.

The TD0245S specification requires that the chipselect is toggled
between commands sent to the panel. This was also the purpose of the
former patch of commit f64dcac0b1 ("backlight: tdo24m: ensure chip
select changes between transfers").

Unfortunately, the "cs_change" field of a SPI transfer is
misleading. Its true meaning is that for a SPI message holding multiple
transfers, the chip select is toggled between each transfer, but for the
last transfer it remains asserted.

In this driver, all the SPI messages contain exactly one transfer, which
means that each transfer is the last of its message, and as a
consequence the chip select is never toggled.

Actually, there was a second bug hidding the first one, hence the
problem was not seen until v4.6. This problem was fixed by commit
a52db659c7 ("spi: pxa2xx: Fix cs_change management") for PXA based
boards.

This fix makes the TD035S work again on a cm-x300 board. The same
applies to other PXA boards, ie. corgi and tosa.

Fixes: a52db659c7 ("spi: pxa2xx: Fix cs_change management")
Reported-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-01-08 09:21:57 +00:00

453 lines
11 KiB
C

/*
* tdo24m - SPI-based drivers for Toppoly TDO24M series LCD panels
*
* Copyright (C) 2008 Marvell International Ltd.
* Eric Miao <eric.miao@marvell.com>
*
* 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
* publishhed by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/spi/tdo24m.h>
#include <linux/fb.h>
#include <linux/lcd.h>
#include <linux/slab.h>
#define POWER_IS_ON(pwr) ((pwr) <= FB_BLANK_NORMAL)
#define TDO24M_SPI_BUFF_SIZE (4)
#define MODE_QVGA 0
#define MODE_VGA 1
struct tdo24m {
struct spi_device *spi_dev;
struct lcd_device *lcd_dev;
struct spi_message msg;
struct spi_transfer xfer;
uint8_t *buf;
int (*adj_mode)(struct tdo24m *lcd, int mode);
int color_invert;
int power;
int mode;
};
/* use bit 30, 31 as the indicator of command parameter number */
#define CMD0(x) ((0 << 30) | (x))
#define CMD1(x, x1) ((1 << 30) | ((x) << 9) | 0x100 | (x1))
#define CMD2(x, x1, x2) ((2 << 30) | ((x) << 18) | 0x20000 |\
((x1) << 9) | 0x100 | (x2))
#define CMD_NULL (-1)
static const uint32_t lcd_panel_reset[] = {
CMD0(0x1), /* reset */
CMD0(0x0), /* nop */
CMD0(0x0), /* nop */
CMD0(0x0), /* nop */
CMD_NULL,
};
static const uint32_t lcd_panel_on[] = {
CMD0(0x29), /* Display ON */
CMD2(0xB8, 0xFF, 0xF9), /* Output Control */
CMD0(0x11), /* Sleep out */
CMD1(0xB0, 0x16), /* Wake */
CMD_NULL,
};
static const uint32_t lcd_panel_off[] = {
CMD0(0x28), /* Display OFF */
CMD2(0xB8, 0x80, 0x02), /* Output Control */
CMD0(0x10), /* Sleep in */
CMD1(0xB0, 0x00), /* Deep stand by in */
CMD_NULL,
};
static const uint32_t lcd_vga_pass_through_tdo24m[] = {
CMD1(0xB0, 0x16),
CMD1(0xBC, 0x80),
CMD1(0xE1, 0x00),
CMD1(0x36, 0x50),
CMD1(0x3B, 0x00),
CMD_NULL,
};
static const uint32_t lcd_qvga_pass_through_tdo24m[] = {
CMD1(0xB0, 0x16),
CMD1(0xBC, 0x81),
CMD1(0xE1, 0x00),
CMD1(0x36, 0x50),
CMD1(0x3B, 0x22),
CMD_NULL,
};
static const uint32_t lcd_vga_transfer_tdo24m[] = {
CMD1(0xcf, 0x02), /* Blanking period control (1) */
CMD2(0xd0, 0x08, 0x04), /* Blanking period control (2) */
CMD1(0xd1, 0x01), /* CKV timing control on/off */
CMD2(0xd2, 0x14, 0x00), /* CKV 1,2 timing control */
CMD2(0xd3, 0x1a, 0x0f), /* OEV timing control */
CMD2(0xd4, 0x1f, 0xaf), /* ASW timing control (1) */
CMD1(0xd5, 0x14), /* ASW timing control (2) */
CMD0(0x21), /* Invert for normally black display */
CMD0(0x29), /* Display on */
CMD_NULL,
};
static const uint32_t lcd_qvga_transfer[] = {
CMD1(0xd6, 0x02), /* Blanking period control (1) */
CMD2(0xd7, 0x08, 0x04), /* Blanking period control (2) */
CMD1(0xd8, 0x01), /* CKV timing control on/off */
CMD2(0xd9, 0x00, 0x08), /* CKV 1,2 timing control */
CMD2(0xde, 0x05, 0x0a), /* OEV timing control */
CMD2(0xdf, 0x0a, 0x19), /* ASW timing control (1) */
CMD1(0xe0, 0x0a), /* ASW timing control (2) */
CMD0(0x21), /* Invert for normally black display */
CMD0(0x29), /* Display on */
CMD_NULL,
};
static const uint32_t lcd_vga_pass_through_tdo35s[] = {
CMD1(0xB0, 0x16),
CMD1(0xBC, 0x80),
CMD1(0xE1, 0x00),
CMD1(0x3B, 0x00),
CMD_NULL,
};
static const uint32_t lcd_qvga_pass_through_tdo35s[] = {
CMD1(0xB0, 0x16),
CMD1(0xBC, 0x81),
CMD1(0xE1, 0x00),
CMD1(0x3B, 0x22),
CMD_NULL,
};
static const uint32_t lcd_vga_transfer_tdo35s[] = {
CMD1(0xcf, 0x02), /* Blanking period control (1) */
CMD2(0xd0, 0x08, 0x04), /* Blanking period control (2) */
CMD1(0xd1, 0x01), /* CKV timing control on/off */
CMD2(0xd2, 0x00, 0x1e), /* CKV 1,2 timing control */
CMD2(0xd3, 0x14, 0x28), /* OEV timing control */
CMD2(0xd4, 0x28, 0x64), /* ASW timing control (1) */
CMD1(0xd5, 0x28), /* ASW timing control (2) */
CMD0(0x21), /* Invert for normally black display */
CMD0(0x29), /* Display on */
CMD_NULL,
};
static const uint32_t lcd_panel_config[] = {
CMD2(0xb8, 0xff, 0xf9), /* Output control */
CMD0(0x11), /* sleep out */
CMD1(0xba, 0x01), /* Display mode (1) */
CMD1(0xbb, 0x00), /* Display mode (2) */
CMD1(0x3a, 0x60), /* Display mode 18-bit RGB */
CMD1(0xbf, 0x10), /* Drive system change control */
CMD1(0xb1, 0x56), /* Booster operation setup */
CMD1(0xb2, 0x33), /* Booster mode setup */
CMD1(0xb3, 0x11), /* Booster frequency setup */
CMD1(0xb4, 0x02), /* Op amp/system clock */
CMD1(0xb5, 0x35), /* VCS voltage */
CMD1(0xb6, 0x40), /* VCOM voltage */
CMD1(0xb7, 0x03), /* External display signal */
CMD1(0xbd, 0x00), /* ASW slew rate */
CMD1(0xbe, 0x00), /* Dummy data for QuadData operation */
CMD1(0xc0, 0x11), /* Sleep out FR count (A) */
CMD1(0xc1, 0x11), /* Sleep out FR count (B) */
CMD1(0xc2, 0x11), /* Sleep out FR count (C) */
CMD2(0xc3, 0x20, 0x40), /* Sleep out FR count (D) */
CMD2(0xc4, 0x60, 0xc0), /* Sleep out FR count (E) */
CMD2(0xc5, 0x10, 0x20), /* Sleep out FR count (F) */
CMD1(0xc6, 0xc0), /* Sleep out FR count (G) */
CMD2(0xc7, 0x33, 0x43), /* Gamma 1 fine tuning (1) */
CMD1(0xc8, 0x44), /* Gamma 1 fine tuning (2) */
CMD1(0xc9, 0x33), /* Gamma 1 inclination adjustment */
CMD1(0xca, 0x00), /* Gamma 1 blue offset adjustment */
CMD2(0xec, 0x01, 0xf0), /* Horizontal clock cycles */
CMD_NULL,
};
static int tdo24m_writes(struct tdo24m *lcd, const uint32_t *array)
{
struct spi_transfer *x = &lcd->xfer;
const uint32_t *p = array;
uint32_t data;
int nparams, err = 0;
for (; *p != CMD_NULL; p++) {
if (!lcd->color_invert && *p == CMD0(0x21))
continue;
nparams = (*p >> 30) & 0x3;
data = *p << (7 - nparams);
switch (nparams) {
case 0:
lcd->buf[0] = (data >> 8) & 0xff;
lcd->buf[1] = data & 0xff;
break;
case 1:
lcd->buf[0] = (data >> 16) & 0xff;
lcd->buf[1] = (data >> 8) & 0xff;
lcd->buf[2] = data & 0xff;
break;
case 2:
lcd->buf[0] = (data >> 24) & 0xff;
lcd->buf[1] = (data >> 16) & 0xff;
lcd->buf[2] = (data >> 8) & 0xff;
lcd->buf[3] = data & 0xff;
break;
default:
continue;
}
x->len = nparams + 2;
err = spi_sync(lcd->spi_dev, &lcd->msg);
if (err)
break;
}
return err;
}
static int tdo24m_adj_mode(struct tdo24m *lcd, int mode)
{
switch (mode) {
case MODE_VGA:
tdo24m_writes(lcd, lcd_vga_pass_through_tdo24m);
tdo24m_writes(lcd, lcd_panel_config);
tdo24m_writes(lcd, lcd_vga_transfer_tdo24m);
break;
case MODE_QVGA:
tdo24m_writes(lcd, lcd_qvga_pass_through_tdo24m);
tdo24m_writes(lcd, lcd_panel_config);
tdo24m_writes(lcd, lcd_qvga_transfer);
break;
default:
return -EINVAL;
}
lcd->mode = mode;
return 0;
}
static int tdo35s_adj_mode(struct tdo24m *lcd, int mode)
{
switch (mode) {
case MODE_VGA:
tdo24m_writes(lcd, lcd_vga_pass_through_tdo35s);
tdo24m_writes(lcd, lcd_panel_config);
tdo24m_writes(lcd, lcd_vga_transfer_tdo35s);
break;
case MODE_QVGA:
tdo24m_writes(lcd, lcd_qvga_pass_through_tdo35s);
tdo24m_writes(lcd, lcd_panel_config);
tdo24m_writes(lcd, lcd_qvga_transfer);
break;
default:
return -EINVAL;
}
lcd->mode = mode;
return 0;
}
static int tdo24m_power_on(struct tdo24m *lcd)
{
int err;
err = tdo24m_writes(lcd, lcd_panel_on);
if (err)
goto out;
err = tdo24m_writes(lcd, lcd_panel_reset);
if (err)
goto out;
err = lcd->adj_mode(lcd, lcd->mode);
out:
return err;
}
static int tdo24m_power_off(struct tdo24m *lcd)
{
return tdo24m_writes(lcd, lcd_panel_off);
}
static int tdo24m_power(struct tdo24m *lcd, int power)
{
int ret = 0;
if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
ret = tdo24m_power_on(lcd);
else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
ret = tdo24m_power_off(lcd);
if (!ret)
lcd->power = power;
return ret;
}
static int tdo24m_set_power(struct lcd_device *ld, int power)
{
struct tdo24m *lcd = lcd_get_data(ld);
return tdo24m_power(lcd, power);
}
static int tdo24m_get_power(struct lcd_device *ld)
{
struct tdo24m *lcd = lcd_get_data(ld);
return lcd->power;
}
static int tdo24m_set_mode(struct lcd_device *ld, struct fb_videomode *m)
{
struct tdo24m *lcd = lcd_get_data(ld);
int mode = MODE_QVGA;
if (m->xres == 640 || m->xres == 480)
mode = MODE_VGA;
if (lcd->mode == mode)
return 0;
return lcd->adj_mode(lcd, mode);
}
static struct lcd_ops tdo24m_ops = {
.get_power = tdo24m_get_power,
.set_power = tdo24m_set_power,
.set_mode = tdo24m_set_mode,
};
static int tdo24m_probe(struct spi_device *spi)
{
struct tdo24m *lcd;
struct spi_message *m;
struct spi_transfer *x;
struct tdo24m_platform_data *pdata;
enum tdo24m_model model;
int err;
pdata = dev_get_platdata(&spi->dev);
if (pdata)
model = pdata->model;
else
model = TDO24M;
spi->bits_per_word = 8;
spi->mode = SPI_MODE_3;
err = spi_setup(spi);
if (err)
return err;
lcd = devm_kzalloc(&spi->dev, sizeof(struct tdo24m), GFP_KERNEL);
if (!lcd)
return -ENOMEM;
lcd->spi_dev = spi;
lcd->power = FB_BLANK_POWERDOWN;
lcd->mode = MODE_VGA; /* default to VGA */
lcd->buf = devm_kzalloc(&spi->dev, TDO24M_SPI_BUFF_SIZE, GFP_KERNEL);
if (lcd->buf == NULL)
return -ENOMEM;
m = &lcd->msg;
x = &lcd->xfer;
spi_message_init(m);
x->cs_change = 0;
x->tx_buf = &lcd->buf[0];
spi_message_add_tail(x, m);
switch (model) {
case TDO24M:
lcd->color_invert = 1;
lcd->adj_mode = tdo24m_adj_mode;
break;
case TDO35S:
lcd->adj_mode = tdo35s_adj_mode;
lcd->color_invert = 0;
break;
default:
dev_err(&spi->dev, "Unsupported model");
return -EINVAL;
}
lcd->lcd_dev = devm_lcd_device_register(&spi->dev, "tdo24m", &spi->dev,
lcd, &tdo24m_ops);
if (IS_ERR(lcd->lcd_dev))
return PTR_ERR(lcd->lcd_dev);
spi_set_drvdata(spi, lcd);
err = tdo24m_power(lcd, FB_BLANK_UNBLANK);
if (err)
return err;
return 0;
}
static int tdo24m_remove(struct spi_device *spi)
{
struct tdo24m *lcd = spi_get_drvdata(spi);
tdo24m_power(lcd, FB_BLANK_POWERDOWN);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int tdo24m_suspend(struct device *dev)
{
struct tdo24m *lcd = dev_get_drvdata(dev);
return tdo24m_power(lcd, FB_BLANK_POWERDOWN);
}
static int tdo24m_resume(struct device *dev)
{
struct tdo24m *lcd = dev_get_drvdata(dev);
return tdo24m_power(lcd, FB_BLANK_UNBLANK);
}
#endif
static SIMPLE_DEV_PM_OPS(tdo24m_pm_ops, tdo24m_suspend, tdo24m_resume);
/* Power down all displays on reboot, poweroff or halt */
static void tdo24m_shutdown(struct spi_device *spi)
{
struct tdo24m *lcd = spi_get_drvdata(spi);
tdo24m_power(lcd, FB_BLANK_POWERDOWN);
}
static struct spi_driver tdo24m_driver = {
.driver = {
.name = "tdo24m",
.pm = &tdo24m_pm_ops,
},
.probe = tdo24m_probe,
.remove = tdo24m_remove,
.shutdown = tdo24m_shutdown,
};
module_spi_driver(tdo24m_driver);
MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("Driver for Toppoly TDO24M LCD Panel");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:tdo24m");