From ec03c2104365ead0a33627c05e685093eed3eaef Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Mon, 3 May 2021 20:21:10 +0300
Subject: [PATCH] staging: fbtft: Rectify GPIO handling
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
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Git-commit: ec03c2104365ead0a33627c05e685093eed3eaef
Patch-mainline: v5.14-rc1
References: git-fixes
The infamous commit c440eee1a7a1 ("Staging: staging: fbtft: Switch to
the GPIO descriptor interface") broke GPIO handling completely.
It has already four commits to rectify and it seems not enough.
In order to fix the mess here we:
1) Set default to "inactive" for all requested pins
2) Fix CS#, RD#, and WR# pins polarity since it's active low
and GPIO descriptor interface takes it into consideration
from the Device Tree or ACPI
3) Consolidate chip activation (CS# assertion) under default
->reset() callback
To summarize the expectations about polarity for GPIOs:
RD# Low
WR# Low
CS# Low
RESET# Low
DC or RS High
RW High
Data 0 .. 15 High
See also Adafruit learning course [1] for the example of the schematics.
While at it, drop unneeded NULL checks, since GPIO API is tolerant to that.
[1]: https://learn.adafruit.com/adafruit-2-8-and-3-2-color-tft-touchscreen-breakout-v2/downloads
Fixes: 92e3e884887c ("Staging: fbtft: Fix GPIO handling")
Fixes: b918d1c27066 ("Staging: fbtft: Fix reset assertion when using gpio descriptor")
Fixes: dbc4f989c878 ("Staging: fbtft: Fix probing of gpio descriptor")
Fixes: c440eee1a7a1 ("Staging: fbtft: Switch to the gpio descriptor interface")
Cc: Jan Sebastian Götte <linux@jaseg.net>
Cc: Nishad Kamdar <nishadkamdar@gmail.com>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210503172114.27891-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/staging/fbtft/fb_agm1264k-fl.c | 20 ++++++++++----------
drivers/staging/fbtft/fb_bd663474.c | 4 ----
drivers/staging/fbtft/fb_ili9163.c | 4 ----
drivers/staging/fbtft/fb_ili9320.c | 1 -
drivers/staging/fbtft/fb_ili9325.c | 4 ----
drivers/staging/fbtft/fb_ili9340.c | 1 -
drivers/staging/fbtft/fb_s6d1121.c | 4 ----
drivers/staging/fbtft/fb_sh1106.c | 1 -
drivers/staging/fbtft/fb_ssd1289.c | 4 ----
drivers/staging/fbtft/fb_ssd1325.c | 2 --
drivers/staging/fbtft/fb_ssd1331.c | 6 ++----
drivers/staging/fbtft/fb_ssd1351.c | 1 -
drivers/staging/fbtft/fb_upd161704.c | 4 ----
drivers/staging/fbtft/fb_watterott.c | 1 -
drivers/staging/fbtft/fbtft-bus.c | 3 +--
drivers/staging/fbtft/fbtft-core.c | 13 ++++++-------
drivers/staging/fbtft/fbtft-io.c | 12 ++++++------
17 files changed, 25 insertions(+), 60 deletions(-)
--- a/drivers/staging/fbtft/fb_agm1264k-fl.c
+++ b/drivers/staging/fbtft/fb_agm1264k-fl.c
@@ -84,9 +84,9 @@ static void reset(struct fbtft_par *par)
dev_dbg(par->info->device, "%s()\n", __func__);
- gpiod_set_value(par->gpio.reset, 0);
- udelay(20);
gpiod_set_value(par->gpio.reset, 1);
+ udelay(20);
+ gpiod_set_value(par->gpio.reset, 0);
mdelay(120);
}
@@ -194,12 +194,12 @@ static void write_reg8_bus8(struct fbtft
/* select chip */
if (*buf) {
/* cs1 */
- gpiod_set_value(par->CS0, 1);
- gpiod_set_value(par->CS1, 0);
- } else {
- /* cs0 */
gpiod_set_value(par->CS0, 0);
gpiod_set_value(par->CS1, 1);
+ } else {
+ /* cs0 */
+ gpiod_set_value(par->CS0, 1);
+ gpiod_set_value(par->CS1, 0);
}
gpiod_set_value(par->RS, 0); /* RS->0 (command mode) */
@@ -397,8 +397,8 @@ static int write_vmem(struct fbtft_par *
}
kfree(convert_buf);
- gpiod_set_value(par->CS0, 1);
- gpiod_set_value(par->CS1, 1);
+ gpiod_set_value(par->CS0, 0);
+ gpiod_set_value(par->CS1, 0);
return ret;
}
@@ -419,10 +419,10 @@ static int write(struct fbtft_par *par,
for (i = 0; i < 8; ++i)
gpiod_set_value(par->gpio.db[i], data & (1 << i));
/* set E */
- gpiod_set_value(par->EPIN, 1);
+ gpiod_set_value(par->EPIN, 0);
udelay(5);
/* unset E - write */
- gpiod_set_value(par->EPIN, 0);
+ gpiod_set_value(par->EPIN, 1);
udelay(1);
}
--- a/drivers/staging/fbtft/fb_bd663474.c
+++ b/drivers/staging/fbtft/fb_bd663474.c
@@ -12,7 +12,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
@@ -24,9 +23,6 @@
static int init_display(struct fbtft_par *par)
{
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
par->fbtftops.reset(par);
/* Initialization sequence from Lib_UTFT */
--- a/drivers/staging/fbtft/fb_ili9163.c
+++ b/drivers/staging/fbtft/fb_ili9163.c
@@ -11,7 +11,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include <video/mipi_display.h>
@@ -77,9 +76,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
write_reg(par, MIPI_DCS_SOFT_RESET); /* software reset */
mdelay(500);
write_reg(par, MIPI_DCS_EXIT_SLEEP_MODE); /* exit sleep */
--- a/drivers/staging/fbtft/fb_ili9320.c
+++ b/drivers/staging/fbtft/fb_ili9320.c
@@ -8,7 +8,6 @@
#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>
--- a/drivers/staging/fbtft/fb_ili9325.c
+++ b/drivers/staging/fbtft/fb_ili9325.c
@@ -10,7 +10,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
@@ -85,9 +84,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
bt &= 0x07;
vc &= 0x07;
vrh &= 0x0f;
--- a/drivers/staging/fbtft/fb_ili9340.c
+++ b/drivers/staging/fbtft/fb_ili9340.c
@@ -8,7 +8,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include <video/mipi_display.h>
--- a/drivers/staging/fbtft/fb_s6d1121.c
+++ b/drivers/staging/fbtft/fb_s6d1121.c
@@ -12,7 +12,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
@@ -29,9 +28,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
/* Initialization sequence from Lib_UTFT */
write_reg(par, 0x0011, 0x2004);
--- a/drivers/staging/fbtft/fb_sh1106.c
+++ b/drivers/staging/fbtft/fb_sh1106.c
@@ -9,7 +9,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
--- a/drivers/staging/fbtft/fb_ssd1289.c
+++ b/drivers/staging/fbtft/fb_ssd1289.c
@@ -10,7 +10,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include "fbtft.h"
@@ -28,9 +27,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
write_reg(par, 0x00, 0x0001);
write_reg(par, 0x03, 0xA8A4);
write_reg(par, 0x0C, 0x0000);
--- a/drivers/staging/fbtft/fb_ssd1325.c
+++ b/drivers/staging/fbtft/fb_ssd1325.c
@@ -35,8 +35,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- gpiod_set_value(par->gpio.cs, 0);
-
write_reg(par, 0xb3);
write_reg(par, 0xf0);
write_reg(par, 0xae);
--- a/drivers/staging/fbtft/fb_ssd1331.c
+++ b/drivers/staging/fbtft/fb_ssd1331.c
@@ -81,8 +81,7 @@ static void write_reg8_bus8(struct fbtft
va_start(args, len);
*buf = (u8)va_arg(args, unsigned int);
- if (par->gpio.dc)
- gpiod_set_value(par->gpio.dc, 0);
+ gpiod_set_value(par->gpio.dc, 0);
ret = par->fbtftops.write(par, par->buf, sizeof(u8));
if (ret < 0) {
va_end(args);
@@ -104,8 +103,7 @@ static void write_reg8_bus8(struct fbtft
return;
}
}
- if (par->gpio.dc)
- gpiod_set_value(par->gpio.dc, 1);
+ gpiod_set_value(par->gpio.dc, 1);
va_end(args);
}
--- a/drivers/staging/fbtft/fb_ssd1351.c
+++ b/drivers/staging/fbtft/fb_ssd1351.c
@@ -2,7 +2,6 @@
#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>
--- a/drivers/staging/fbtft/fb_upd161704.c
+++ b/drivers/staging/fbtft/fb_upd161704.c
@@ -12,7 +12,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
@@ -26,9 +25,6 @@ static int init_display(struct fbtft_par
{
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
-
/* Initialization sequence from Lib_UTFT */
/* register reset */
--- a/drivers/staging/fbtft/fb_watterott.c
+++ b/drivers/staging/fbtft/fb_watterott.c
@@ -8,7 +8,6 @@
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "fbtft.h"
--- a/drivers/staging/fbtft/fbtft-bus.c
+++ b/drivers/staging/fbtft/fbtft-bus.c
@@ -135,8 +135,7 @@ int fbtft_write_vmem16_bus8(struct fbtft
remain = len / 2;
vmem16 = (u16 *)(par->info->screen_buffer + offset);
- if (par->gpio.dc)
- gpiod_set_value(par->gpio.dc, 1);
+ gpiod_set_value(par->gpio.dc, 1);
/* non buffered write */
if (!par->txbuf.buf)
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -37,8 +37,7 @@ int fbtft_write_buf_dc(struct fbtft_par
{
int ret;
- if (par->gpio.dc)
- gpiod_set_value(par->gpio.dc, dc);
+ gpiod_set_value(par->gpio.dc, dc);
ret = par->fbtftops.write(par, buf, len);
if (ret < 0)
@@ -79,7 +78,7 @@ static int fbtft_request_one_gpio(struct
int ret = 0;
*gpiop = devm_gpiod_get_index_optional(dev, name, index,
- GPIOD_OUT_HIGH);
+ GPIOD_OUT_LOW);
if (IS_ERR(*gpiop)) {
ret = PTR_ERR(*gpiop);
dev_err(dev,
@@ -230,11 +229,15 @@ static void fbtft_reset(struct fbtft_par
{
if (!par->gpio.reset)
return;
+
fbtft_par_dbg(DEBUG_RESET, par, "%s()\n", __func__);
+
gpiod_set_value_cansleep(par->gpio.reset, 1);
usleep_range(20, 40);
gpiod_set_value_cansleep(par->gpio.reset, 0);
msleep(120);
+
+ gpiod_set_value_cansleep(par->gpio.cs, 1); /* Activate chip */
}
static void fbtft_update_display(struct fbtft_par *par, unsigned int start_line,
@@ -921,8 +924,6 @@ static int fbtft_init_display_dt(struct
return -EINVAL;
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
while (p) {
if (val & FBTFT_OF_INIT_CMD) {
@@ -1012,8 +1013,6 @@ int fbtft_init_display(struct fbtft_par
}
par->fbtftops.reset(par);
- if (par->gpio.cs)
- gpiod_set_value(par->gpio.cs, 0); /* Activate chip */
i = 0;
while (i < FBTFT_MAX_INIT_SEQUENCE) {
--- a/drivers/staging/fbtft/fbtft-io.c
+++ b/drivers/staging/fbtft/fbtft-io.c
@@ -142,12 +142,12 @@ int fbtft_write_gpio8_wr(struct fbtft_pa
data = *(u8 *)buf;
/* Start writing by pulling down /WR */
- gpiod_set_value(par->gpio.wr, 0);
+ gpiod_set_value(par->gpio.wr, 1);
/* Set data */
#ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO
if (data == prev_data) {
- gpiod_set_value(par->gpio.wr, 0); /* used as delay */
+ gpiod_set_value(par->gpio.wr, 1); /* used as delay */
} else {
for (i = 0; i < 8; i++) {
if ((data & 1) != (prev_data & 1))
@@ -165,7 +165,7 @@ int fbtft_write_gpio8_wr(struct fbtft_pa
#endif
/* Pullup /WR */
- gpiod_set_value(par->gpio.wr, 1);
+ gpiod_set_value(par->gpio.wr, 0);
#ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO
prev_data = *(u8 *)buf;
@@ -192,12 +192,12 @@ int fbtft_write_gpio16_wr(struct fbtft_p
data = *(u16 *)buf;
/* Start writing by pulling down /WR */
- gpiod_set_value(par->gpio.wr, 0);
+ gpiod_set_value(par->gpio.wr, 1);
/* Set data */
#ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO
if (data == prev_data) {
- gpiod_set_value(par->gpio.wr, 0); /* used as delay */
+ gpiod_set_value(par->gpio.wr, 1); /* used as delay */
} else {
for (i = 0; i < 16; i++) {
if ((data & 1) != (prev_data & 1))
@@ -215,7 +215,7 @@ int fbtft_write_gpio16_wr(struct fbtft_p
#endif
/* Pullup /WR */
- gpiod_set_value(par->gpio.wr, 1);
+ gpiod_set_value(par->gpio.wr, 0);
#ifndef DO_NOT_OPTIMIZE_FBTFT_WRITE_GPIO
prev_data = *(u16 *)buf;