[PATCH 1/2] gpio: Drop long unused DB8500 GPIO driver

[PATCH 1/2] gpio: Drop long unused DB8500 GPIO driver

[Stephan Gerhold]

The original U-Boot port for the ST-Ericsson U8500 SoC was dropped
in commit 68282f55b846 ("arm: Remove unused ST-Ericsson u8500 arch").
Most of the drivers related to the old port were removed, but the
db8500_gpio.c driver was forgotten for some reason. There is no way
to select it and it does not compile anymore because of missing
headers, so let's just remove it.

The new port for U8500 introduced in commit 689088f9dae8
("arm: Add support for ST-Ericsson U8500 SoC") fully embraces the
new Driver Model and device trees where possible, so this is
preparation to add a new, simplified GPIO driver based on DM_GPIO.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---

 drivers/gpio/Makefile      |   1 -
 drivers/gpio/db8500_gpio.c | 221 -------------------------------------
 2 files changed, 222 deletions(-)
 delete mode 100644 drivers/gpio/db8500_gpio.c

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 8541ba0b0a..3da0d2eb33 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -44,7 +44,6 @@ obj-$(CONFIG_MPC8XXX_GPIO)	+= mpc8xxx_gpio.o
 obj-$(CONFIG_MPC83XX_SPISEL_BOOT)	+= mpc83xx_spisel_boot.o
 obj-$(CONFIG_SH_GPIO_PFC)	+= sh_pfc.o
 obj-$(CONFIG_OMAP_GPIO)	+= omap_gpio.o
-obj-$(CONFIG_DB8500_GPIO)	+= db8500_gpio.o
 obj-$(CONFIG_BCM2835_GPIO)	+= bcm2835_gpio.o
 obj-$(CONFIG_XILINX_GPIO)	+= xilinx_gpio.o
 obj-$(CONFIG_ADI_GPIO2)	+= adi_gpio2.o
diff --git a/drivers/gpio/db8500_gpio.c b/drivers/gpio/db8500_gpio.c
deleted file mode 100644
index eefb56d83f..0000000000
--- a/drivers/gpio/db8500_gpio.c
+++ /dev/null
@@ -1,221 +0,0 @@
-/*
- * Code ported from Nomadik GPIO driver in ST-Ericsson Linux kernel code.
- * The purpose is that GPIO config found in kernel should work by simply
- * copy-paste it to U-Boot.
- *
- * Original Linux authors:
- * Copyright (C) 2008,2009 STMicroelectronics
- * Copyright (C) 2009 Alessandro Rubini <rubini@unipv.it>
- *   Rewritten based on work by Prafulla WADASKAR <prafulla.wadaskar@st.com>
- *
- * Ported to U-Boot by:
- * Copyright (C) 2010 Joakim Axelsson <joakim.axelsson AT stericsson.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
- * published by the Free Software Foundation.
- */
-
-#include <common.h>
-#include <asm/io.h>
-
-#include <asm/arch/db8500_gpio.h>
-#include <asm/arch/db8500_pincfg.h>
-#include <linux/compiler.h>
-
-#define IO_ADDR(x) (void *) (x)
-
-/*
- * The GPIO module in the db8500 Systems-on-Chip is an
- * AMBA device, managing 32 pins and alternate functions. The logic block
- * is currently only used in the db8500.
- */
-
-#define GPIO_TOTAL_PINS		268
-#define GPIO_PINS_PER_BLOCK	32
-#define GPIO_BLOCKS_COUNT	(GPIO_TOTAL_PINS/GPIO_PINS_PER_BLOCK + 1)
-#define GPIO_BLOCK(pin)		(((pin + GPIO_PINS_PER_BLOCK) >> 5) - 1)
-#define GPIO_PIN_WITHIN_BLOCK(pin)	((pin)%(GPIO_PINS_PER_BLOCK))
-
-/* Register in the logic block */
-#define DB8500_GPIO_DAT		0x00
-#define DB8500_GPIO_DATS	0x04
-#define DB8500_GPIO_DATC	0x08
-#define DB8500_GPIO_PDIS	0x0c
-#define DB8500_GPIO_DIR		0x10
-#define DB8500_GPIO_DIRS	0x14
-#define DB8500_GPIO_DIRC	0x18
-#define DB8500_GPIO_SLPC	0x1c
-#define DB8500_GPIO_AFSLA	0x20
-#define DB8500_GPIO_AFSLB	0x24
-
-#define DB8500_GPIO_RIMSC	0x40
-#define DB8500_GPIO_FIMSC	0x44
-#define DB8500_GPIO_IS		0x48
-#define DB8500_GPIO_IC		0x4c
-#define DB8500_GPIO_RWIMSC	0x50
-#define DB8500_GPIO_FWIMSC	0x54
-#define DB8500_GPIO_WKS		0x58
-
-static void __iomem *get_gpio_addr(unsigned gpio)
-{
-	/* Our list of GPIO chips */
-	static void __iomem *gpio_addrs[GPIO_BLOCKS_COUNT] = {
-		IO_ADDR(CFG_GPIO_0_BASE),
-		IO_ADDR(CFG_GPIO_1_BASE),
-		IO_ADDR(CFG_GPIO_2_BASE),
-		IO_ADDR(CFG_GPIO_3_BASE),
-		IO_ADDR(CFG_GPIO_4_BASE),
-		IO_ADDR(CFG_GPIO_5_BASE),
-		IO_ADDR(CFG_GPIO_6_BASE),
-		IO_ADDR(CFG_GPIO_7_BASE),
-		IO_ADDR(CFG_GPIO_8_BASE)
-	};
-
-	return gpio_addrs[GPIO_BLOCK(gpio)];
-}
-
-static unsigned get_gpio_offset(unsigned gpio)
-{
-	return GPIO_PIN_WITHIN_BLOCK(gpio);
-}
-
-/* Can only be called from config_pin. Don't configure alt-mode directly */
-static void gpio_set_mode(unsigned gpio, enum db8500_gpio_alt mode)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-	u32 bit = 1 << offset;
-	u32 afunc, bfunc;
-
-	afunc = readl(addr + DB8500_GPIO_AFSLA) & ~bit;
-	bfunc = readl(addr + DB8500_GPIO_AFSLB) & ~bit;
-	if (mode & DB8500_GPIO_ALT_A)
-		afunc |= bit;
-	if (mode & DB8500_GPIO_ALT_B)
-		bfunc |= bit;
-	writel(afunc, addr + DB8500_GPIO_AFSLA);
-	writel(bfunc, addr + DB8500_GPIO_AFSLB);
-}
-
-/**
- * db8500_gpio_set_pull() - enable/disable pull up/down on a gpio
- * @gpio: pin number
- * @pull: one of DB8500_GPIO_PULL_DOWN, DB8500_GPIO_PULL_UP,
- *  and DB8500_GPIO_PULL_NONE
- *
- * Enables/disables pull up/down on a specified pin.  This only takes effect if
- * the pin is configured as an input (either explicitly or by the alternate
- * function).
- *
- * NOTE: If enabling the pull up/down, the caller must ensure that the GPIO is
- * configured as an input.  Otherwise, due to the way the controller registers
- * work, this function will change the value output on the pin.
- */
-void db8500_gpio_set_pull(unsigned gpio, enum db8500_gpio_pull pull)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-	u32 bit = 1 << offset;
-	u32 pdis;
-
-	pdis = readl(addr + DB8500_GPIO_PDIS);
-	if (pull == DB8500_GPIO_PULL_NONE)
-		pdis |= bit;
-	else
-		pdis &= ~bit;
-	writel(pdis, addr + DB8500_GPIO_PDIS);
-
-	if (pull == DB8500_GPIO_PULL_UP)
-		writel(bit, addr + DB8500_GPIO_DATS);
-	else if (pull == DB8500_GPIO_PULL_DOWN)
-		writel(bit, addr + DB8500_GPIO_DATC);
-}
-
-void db8500_gpio_make_input(unsigned gpio)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-
-	writel(1 << offset, addr + DB8500_GPIO_DIRC);
-}
-
-int db8500_gpio_get_input(unsigned gpio)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-	u32 bit = 1 << offset;
-
-	printf("db8500_gpio_get_input gpio=%u addr=%p offset=%u bit=%#x\n",
-		gpio, addr, offset, bit);
-
-	return (readl(addr + DB8500_GPIO_DAT) & bit) != 0;
-}
-
-void db8500_gpio_make_output(unsigned gpio, int val)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-
-	writel(1 << offset, addr + DB8500_GPIO_DIRS);
-	db8500_gpio_set_output(gpio, val);
-}
-
-void db8500_gpio_set_output(unsigned gpio, int val)
-{
-	void __iomem *addr = get_gpio_addr(gpio);
-	unsigned offset = get_gpio_offset(gpio);
-
-	if (val)
-		writel(1 << offset, addr + DB8500_GPIO_DATS);
-	else
-		writel(1 << offset, addr + DB8500_GPIO_DATC);
-}
-
-/**
- * config_pin - configure a pin's mux attributes
- * @cfg: pin configuration
- *
- * Configures a pin's mode (alternate function or GPIO), its pull up status,
- * and its sleep mode based on the specified configuration.  The @cfg is
- * usually one of the SoC specific macros defined in mach/<soc>-pins.h.  These
- * are constructed using, and can be further enhanced with, the macros in
- * plat/pincfg.h.
- *
- * If a pin's mode is set to GPIO, it is configured as an input to avoid
- * side-effects.  The gpio can be manipulated later using standard GPIO API
- * calls.
- */
-static void config_pin(unsigned long cfg)
-{
-	int pin = PIN_NUM(cfg);
-	int pull = PIN_PULL(cfg);
-	int af = PIN_ALT(cfg);
-	int output = PIN_DIR(cfg);
-	int val = PIN_VAL(cfg);
-
-	if (output)
-		db8500_gpio_make_output(pin, val);
-	else {
-		db8500_gpio_make_input(pin);
-		db8500_gpio_set_pull(pin, pull);
-	}
-
-	gpio_set_mode(pin, af);
-}
-
-/**
- * db8500_config_pins - configure several pins at once
- * @cfgs: array of pin configurations
- * @num: number of elments in the array
- *
- * Configures several pins using config_pin(). Refer to that function for
- * further information.
- */
-void db8500_gpio_config_pins(unsigned long *cfgs, size_t num)
-{
-	size_t i;
-
-	for (i = 0; i < num; i++)
-		config_pin(cfgs[i]);
-}
-- 
2.32.0

[PATCH 2/2] gpio: Add driver for Nomadik GPIO

[Stephan Gerhold]

Nomadik GPIO is a fairly simple GPIO module used in the ST-Ericsson
Ux500 SoCs (and some older Nomadik SoCs). It uses registers where
each GPIO is represented as a single bit, plus "set" and "clear"
registers that allow updating the state without having to read the
existing state.

The driver implements support for it for use together with DM_GPIO
and the existing ste-dbx5x0.dtsi device tree.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---

 drivers/gpio/Kconfig    |   8 +++
 drivers/gpio/Makefile   |   1 +
 drivers/gpio/nmk_gpio.c | 125 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 134 insertions(+)
 create mode 100644 drivers/gpio/nmk_gpio.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index de4dc51d4b..0817b12c5f 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -495,4 +495,12 @@ config NX_GPIO
 	  The GPIOs for a device are defined in the device tree with one node
 	  for each bank.
 
+config NOMADIK_GPIO
+	bool "Nomadik GPIO driver"
+	depends on DM_GPIO
+	help
+	  Support GPIO access on ST-Ericsson Ux500 SoCs. The GPIOs are arranged
+	  into a number of banks each with 32 GPIOs. The GPIOs for a device are
+	  defined in the device tree with one node for each bank.
+
 endmenu
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 3da0d2eb33..3de9734724 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -68,3 +68,4 @@ obj-$(CONFIG_MT7621_GPIO)	+= mt7621_gpio.o
 obj-$(CONFIG_MSCC_SGPIO)	+= mscc_sgpio.o
 obj-$(CONFIG_NX_GPIO)		+= nx_gpio.o
 obj-$(CONFIG_SIFIVE_GPIO)	+= sifive-gpio.o
+obj-$(CONFIG_NOMADIK_GPIO)	+= nmk_gpio.o
diff --git a/drivers/gpio/nmk_gpio.c b/drivers/gpio/nmk_gpio.c
new file mode 100644
index 0000000000..e1bb41b196
--- /dev/null
+++ b/drivers/gpio/nmk_gpio.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2019 Stephan Gerhold */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+struct nmk_gpio_regs {
+	u32 dat;	/* data */
+	u32 dats;	/* data set */
+	u32 datc;	/* data clear */
+	u32 pdis;	/* pull disable */
+	u32 dir;	/* direction */
+	u32 dirs;	/* direction set */
+	u32 dirc;	/* direction clear */
+	u32 slpm;	/* sleep mode */
+	u32 afsla;	/* alternate function select A */
+	u32 afslb;	/* alternate function select B */
+	u32 lowemi;	/* low EMI mode */
+};
+
+struct nmk_gpio {
+	struct nmk_gpio_regs *regs;
+};
+
+static int nmk_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+
+	return !!(readl(&priv->regs->dat) & BIT(offset));
+}
+
+static int nmk_gpio_set_value(struct udevice *dev, unsigned offset, int value)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+
+	if (value)
+		writel(BIT(offset), &priv->regs->dats);
+	else
+		writel(BIT(offset), &priv->regs->datc);
+
+	return 0;
+}
+
+static int nmk_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+
+	if (readl(&priv->regs->afsla) & BIT(offset) ||
+	    readl(&priv->regs->afslb) & BIT(offset))
+		return GPIOF_FUNC;
+
+	if (readl(&priv->regs->dir) & BIT(offset))
+		return GPIOF_OUTPUT;
+	else
+		return GPIOF_INPUT;
+}
+
+static int nmk_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+
+	writel(BIT(offset), &priv->regs->dirc);
+	return 0;
+}
+
+static int nmk_gpio_direction_output(struct udevice *dev, unsigned offset,
+				     int value)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+
+	writel(BIT(offset), &priv->regs->dirs);
+	return nmk_gpio_set_value(dev, offset, value);
+}
+
+static const struct dm_gpio_ops nmk_gpio_ops = {
+	.get_value		= nmk_gpio_get_value,
+	.set_value		= nmk_gpio_set_value,
+	.get_function		= nmk_gpio_get_function,
+	.direction_input	= nmk_gpio_direction_input,
+	.direction_output	= nmk_gpio_direction_output,
+};
+
+static int nmk_gpio_probe(struct udevice *dev)
+{
+	struct nmk_gpio *priv = dev_get_priv(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	char buf[20];
+	u32 bank;
+	int ret;
+
+	priv->regs = dev_read_addr_ptr(dev);
+	if (!priv->regs)
+		return -EINVAL;
+
+	ret = dev_read_u32(dev, "gpio-bank", &bank);
+	if (ret < 0) {
+		printf("nmk_gpio(%s): Failed to read gpio-bank\n", dev->name);
+		return ret;
+	}
+
+	sprintf(buf, "nmk%u-gpio", bank);
+	uc_priv->bank_name = strdup(buf);
+	if (!uc_priv->bank_name)
+		return -ENOMEM;
+
+	uc_priv->gpio_count = sizeof(priv->regs->dat) * BITS_PER_BYTE;
+
+	return 0;
+}
+
+static const struct udevice_id nmk_gpio_ids[] = {
+	{ .compatible = "st,nomadik-gpio" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpio_nmk) = {
+	.name		= "nmk_gpio",
+	.id		= UCLASS_GPIO,
+	.of_match	= nmk_gpio_ids,
+	.probe		= nmk_gpio_probe,
+	.ops		= &nmk_gpio_ops,
+	.priv_auto	= sizeof(struct nmk_gpio),
+};
-- 
2.32.0

Re: [PATCH 1/2] gpio: Drop long unused DB8500 GPIO driver

[Linus Walleij]

On Fri, Jul 2, 2021 at 5:06 PM Stephan Gerhold <stephan@gerhold.net> wrote:

> The original U-Boot port for the ST-Ericsson U8500 SoC was dropped
> in commit 68282f55b846 ("arm: Remove unused ST-Ericsson u8500 arch").
> Most of the drivers related to the old port were removed, but the
> db8500_gpio.c driver was forgotten for some reason. There is no way
> to select it and it does not compile anymore because of missing
> headers, so let's just remove it.
>
> The new port for U8500 introduced in commit 689088f9dae8
> ("arm: Add support for ST-Ericsson U8500 SoC") fully embraces the
> new Driver Model and device trees where possible, so this is
> preparation to add a new, simplified GPIO driver based on DM_GPIO.
>
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH 2/2] gpio: Add driver for Nomadik GPIO

[Linus Walleij]

On Fri, Jul 2, 2021 at 5:06 PM Stephan Gerhold <stephan@gerhold.net> wrote:

> Nomadik GPIO is a fairly simple GPIO module used in the ST-Ericsson
> Ux500 SoCs (and some older Nomadik SoCs). It uses registers where
> each GPIO is represented as a single bit, plus "set" and "clear"
> registers that allow updating the state without having to read the
> existing state.
>
> The driver implements support for it for use together with DM_GPIO
> and the existing ste-dbx5x0.dtsi device tree.
>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH 1/2] gpio: Drop long unused DB8500 GPIO driver

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 888 bytes --]

On Fri, Jul 02, 2021 at 05:06:17PM +0200, Stephan Gerhold wrote:

> The original U-Boot port for the ST-Ericsson U8500 SoC was dropped
> in commit 68282f55b846 ("arm: Remove unused ST-Ericsson u8500 arch").
> Most of the drivers related to the old port were removed, but the
> db8500_gpio.c driver was forgotten for some reason. There is no way
> to select it and it does not compile anymore because of missing
> headers, so let's just remove it.
> 
> The new port for U8500 introduced in commit 689088f9dae8
> ("arm: Add support for ST-Ericsson U8500 SoC") fully embraces the
> new Driver Model and device trees where possible, so this is
> preparation to add a new, simplified GPIO driver based on DM_GPIO.
> 
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Applied to u-boot/master, thanks!

-- 
Tom

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Re: [PATCH 2/2] gpio: Add driver for Nomadik GPIO

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 702 bytes --]

On Fri, Jul 02, 2021 at 05:06:18PM +0200, Stephan Gerhold wrote:

> Nomadik GPIO is a fairly simple GPIO module used in the ST-Ericsson
> Ux500 SoCs (and some older Nomadik SoCs). It uses registers where
> each GPIO is represented as a single bit, plus "set" and "clear"
> registers that allow updating the state without having to read the
> existing state.
> 
> The driver implements support for it for use together with DM_GPIO
> and the existing ste-dbx5x0.dtsi device tree.
> 
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Applied to u-boot/master, thanks!

-- 
Tom

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