Commit e1b2dc70 authored by Simon Arlott's avatar Simon Arlott Committed by Linus Walleij

pinctrl: add bcm2835 driver

The BCM2835 GPIO module is a combined GPIO controller, (GPIO) interrupt
controller, and pinmux/control device.

Original driver by Simon Arlott.
Rewrite including GPIO chip device by Chris Boot.

Upstreaming changes by Stephen Warren:
* Wrote DT binding documentation.
* Changed brcm,function to an integer to more directly match the
  datasheet, and to match brcm,pins being an integer.
* Implemented pull-up/down pin config.
* Removed read-only DT property and related code. The restriction this
  implemented are driven by the board, not the GPIO HW block, so don't
  really make sense of a HW block binding, were in general incomplete
  (since they could only know about the few pins hard-coded into the
  Raspberry Pi B board design and not the uncommitted GPIOS), and are
  better represented simply by not writing incorrect data into pin
  configuration nodes.
* Don't set GPIO_IN function select in gpio_request_enable() to avoid
  glitches; defer this to gpio_set_direction(). Consequently, removed
  empty bcm2835_pmx_gpio_request_enable().
* Simplified enabled_irq_map[]; make it explicitly 1 entry per bank.
* Lifted use of enabled_irq_map[] outside the per-interrupt loop in
  IRQ handler, thus fixing an issue where the code was indexing into
  enabled_irq_map[] by intra-bank GPIO ID, not global GPIO ID.
* Removed locking in IRQ handler, since all other code uses
  spin_lock_irqsave() and so guarantees it doesn't run concurrently
  with the handler.
* Moved duplicated BUILD_BUG_ON()s into probe(). Also check size of
  bcm2835_gpio_pins[].
* Remove range-checking from bcm2835_pctl_get_groups_count() since we've
  decided to trust the pinctrl core.
* Made bcm2835_pmx_gpio_disable_free() call bcm2835_pinctrl_fsel_set()
  directly for simplicity.
* Fixed body of dt_free_map() to match latest dt_node_to_map().
* Removed GPIO ownership check from bcm2835_pmx_enable() since the pinctrl
  core owns doing this.
* Made irq_chip and pinctrl_gpio_range .name == MODULE_NAME so it's more
  descriptive.
* Simplified remove(); removed call to non-existent
  pinctrl_remove_gpio_range(), remove early return on error.
* Don't force gpiochip's base to 0. Set gpio_range.base to gpiochip's
  base GPIO number.
* Error-handling cleanups in probe().
* Switched to module_platform_driver() rather than open-coding.
* Made pin, group, and function names lower-case.
* s/broadcom/brcm/ in DT property names.
* s/2708/2835/.
* Fixed a couple minor checkpatch warnings, and other minor cleanup.
Signed-off-by: default avatarSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: default avatarChris Boot <bootc@bootc.net>
Signed-off-by: default avatarStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent b0e181d0
Broadcom BCM2835 GPIO (and pinmux) controller
The BCM2835 GPIO module is a combined GPIO controller, (GPIO) interrupt
controller, and pinmux/control device.
Required properties:
- compatible: "brcm,bcm2835-gpio"
- reg: Should contain the physical address of the GPIO module's registes.
- gpio-controller: Marks the device node as a GPIO controller.
- #gpio-cells : Should be two. The first cell is the pin number and the
second cell is used to specify optional parameters:
- bit 0 specifies polarity (0 for normal, 1 for inverted)
- interrupts : The interrupt outputs from the controller. One interrupt per
individual bank followed by the "all banks" interrupt.
- interrupt-controller: Marks the device node as an interrupt controller.
- #interrupt-cells : Should be 2.
The first cell is the GPIO number.
The second cell is used to specify flags:
bits[3:0] trigger type and level flags:
1 = low-to-high edge triggered.
2 = high-to-low edge triggered.
4 = active high level-sensitive.
8 = active low level-sensitive.
Valid combinations are 1, 2, 3, 4, 8.
Please refer to ../gpio/gpio.txt for a general description of GPIO bindings.
Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".
Each pin configuration node lists the pin(s) to which it applies, and one or
more of the mux function to select on those pin(s), and pull-up/down
configuration. Each subnode only affects those parameters that are explicitly
listed. In other words, a subnode that lists only a mux function implies no
information about any pull configuration. Similarly, a subnode that lists only
a pul parameter implies no information about the mux function.
Required subnode-properties:
- brcm,pins: An array of cells. Each cell contains the ID of a pin. Valid IDs
are the integer GPIO IDs; 0==GPIO0, 1==GPIO1, ... 53==GPIO53.
Optional subnode-properties:
- brcm,function: Integer, containing the function to mux to the pin(s):
0: GPIO in
1: GPIO out
2: alt5
3: alt4
4: alt0
5: alt1
6: alt2
7: alt3
- brcm,pull: Integer, representing the pull-down/up to apply to the pin(s):
0: none
1: down
2: up
Each of brcm,function and brcm,pull may contain either a single value which
will be applied to all pins in brcm,pins, or 1 value for each entry in
brcm,pins.
Example:
gpio: gpio {
compatible = "brcm,bcm2835-gpio";
reg = <0x2200000 0xb4>;
interrupts = <2 17>, <2 19>, <2 18>, <2 20>;
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
};
......@@ -26,6 +26,11 @@ config DEBUG_PINCTRL
help
Say Y here to add some extra checks and diagnostics to PINCTRL calls.
config PINCTRL_BCM2835
bool
select PINMUX
select PINCONF
config PINCTRL_IMX
bool
select PINMUX
......
......@@ -9,6 +9,7 @@ ifeq ($(CONFIG_OF),y)
obj-$(CONFIG_PINCTRL) += devicetree.o
endif
obj-$(CONFIG_GENERIC_PINCONF) += pinconf-generic.o
obj-$(CONFIG_PINCTRL_BCM2835) += pinctrl-bcm2835.o
obj-$(CONFIG_PINCTRL_IMX) += pinctrl-imx.o
obj-$(CONFIG_PINCTRL_IMX35) += pinctrl-imx35.o
obj-$(CONFIG_PINCTRL_IMX51) += pinctrl-imx51.o
......
/*
* Driver for Broadcom BCM2835 GPIO unit (pinctrl + GPIO)
*
* Copyright (C) 2012 Chris Boot, Simon Arlott, Stephen Warren
*
* This driver is inspired by:
* pinctrl-nomadik.c, please see original file for copyright information
* pinctrl-tegra.c, please see original file for copyright information
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/bitmap.h>
#include <linux/bug.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdesc.h>
#include <linux/irqdomain.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#define MODULE_NAME "pinctrl-bcm2835"
#define BCM2835_NUM_GPIOS 54
#define BCM2835_NUM_BANKS 2
#define BCM2835_PIN_BITMAP_SZ \
DIV_ROUND_UP(BCM2835_NUM_GPIOS, sizeof(unsigned long) * 8)
/* GPIO register offsets */
#define GPFSEL0 0x0 /* Function Select */
#define GPSET0 0x1c /* Pin Output Set */
#define GPCLR0 0x28 /* Pin Output Clear */
#define GPLEV0 0x34 /* Pin Level */
#define GPEDS0 0x40 /* Pin Event Detect Status */
#define GPREN0 0x4c /* Pin Rising Edge Detect Enable */
#define GPFEN0 0x58 /* Pin Falling Edge Detect Enable */
#define GPHEN0 0x64 /* Pin High Detect Enable */
#define GPLEN0 0x70 /* Pin Low Detect Enable */
#define GPAREN0 0x7c /* Pin Async Rising Edge Detect */
#define GPAFEN0 0x88 /* Pin Async Falling Edge Detect */
#define GPPUD 0x94 /* Pin Pull-up/down Enable */
#define GPPUDCLK0 0x98 /* Pin Pull-up/down Enable Clock */
#define FSEL_REG(p) (GPFSEL0 + (((p) / 10) * 4))
#define FSEL_SHIFT(p) (((p) % 10) * 3)
#define GPIO_REG_OFFSET(p) ((p) / 32)
#define GPIO_REG_SHIFT(p) ((p) % 32)
enum bcm2835_pinconf_param {
/* argument: bcm2835_pinconf_pull */
BCM2835_PINCONF_PARAM_PULL,
};
enum bcm2835_pinconf_pull {
BCM2835_PINCONFIG_PULL_NONE,
BCM2835_PINCONFIG_PULL_DOWN,
BCM2835_PINCONFIG_PULL_UP,
};
#define BCM2835_PINCONF_PACK(_param_, _arg_) ((_param_) << 16 | (_arg_))
#define BCM2835_PINCONF_UNPACK_PARAM(_conf_) ((_conf_) >> 16)
#define BCM2835_PINCONF_UNPACK_ARG(_conf_) ((_conf_) & 0xffff)
struct bcm2835_gpio_irqdata {
struct bcm2835_pinctrl *pc;
int bank;
};
struct bcm2835_pinctrl {
struct device *dev;
void __iomem *base;
int irq[BCM2835_NUM_BANKS];
/* note: locking assumes each bank will have its own unsigned long */
unsigned long enabled_irq_map[BCM2835_NUM_BANKS];
unsigned int irq_type[BCM2835_NUM_GPIOS];
struct pinctrl_dev *pctl_dev;
struct irq_domain *irq_domain;
struct gpio_chip gpio_chip;
struct pinctrl_gpio_range gpio_range;
struct bcm2835_gpio_irqdata irq_data[BCM2835_NUM_BANKS];
spinlock_t irq_lock[BCM2835_NUM_BANKS];
};
static struct lock_class_key gpio_lock_class;
/* pins are just named GPIO0..GPIO53 */
#define BCM2835_GPIO_PIN(a) PINCTRL_PIN(a, "gpio" #a)
struct pinctrl_pin_desc bcm2835_gpio_pins[] = {
BCM2835_GPIO_PIN(0),
BCM2835_GPIO_PIN(1),
BCM2835_GPIO_PIN(2),
BCM2835_GPIO_PIN(3),
BCM2835_GPIO_PIN(4),
BCM2835_GPIO_PIN(5),
BCM2835_GPIO_PIN(6),
BCM2835_GPIO_PIN(7),
BCM2835_GPIO_PIN(8),
BCM2835_GPIO_PIN(9),
BCM2835_GPIO_PIN(10),
BCM2835_GPIO_PIN(11),
BCM2835_GPIO_PIN(12),
BCM2835_GPIO_PIN(13),
BCM2835_GPIO_PIN(14),
BCM2835_GPIO_PIN(15),
BCM2835_GPIO_PIN(16),
BCM2835_GPIO_PIN(17),
BCM2835_GPIO_PIN(18),
BCM2835_GPIO_PIN(19),
BCM2835_GPIO_PIN(20),
BCM2835_GPIO_PIN(21),
BCM2835_GPIO_PIN(22),
BCM2835_GPIO_PIN(23),
BCM2835_GPIO_PIN(24),
BCM2835_GPIO_PIN(25),
BCM2835_GPIO_PIN(26),
BCM2835_GPIO_PIN(27),
BCM2835_GPIO_PIN(28),
BCM2835_GPIO_PIN(29),
BCM2835_GPIO_PIN(30),
BCM2835_GPIO_PIN(31),
BCM2835_GPIO_PIN(32),
BCM2835_GPIO_PIN(33),
BCM2835_GPIO_PIN(34),
BCM2835_GPIO_PIN(35),
BCM2835_GPIO_PIN(36),
BCM2835_GPIO_PIN(37),
BCM2835_GPIO_PIN(38),
BCM2835_GPIO_PIN(39),
BCM2835_GPIO_PIN(40),
BCM2835_GPIO_PIN(41),
BCM2835_GPIO_PIN(42),
BCM2835_GPIO_PIN(43),
BCM2835_GPIO_PIN(44),
BCM2835_GPIO_PIN(45),
BCM2835_GPIO_PIN(46),
BCM2835_GPIO_PIN(47),
BCM2835_GPIO_PIN(48),
BCM2835_GPIO_PIN(49),
BCM2835_GPIO_PIN(50),
BCM2835_GPIO_PIN(51),
BCM2835_GPIO_PIN(52),
BCM2835_GPIO_PIN(53),
};
/* one pin per group */
static const char * const bcm2835_gpio_groups[] = {
"gpio0",
"gpio1",
"gpio2",
"gpio3",
"gpio4",
"gpio5",
"gpio6",
"gpio7",
"gpio8",
"gpio9",
"gpio10",
"gpio11",
"gpio12",
"gpio13",
"gpio14",
"gpio15",
"gpio16",
"gpio17",
"gpio18",
"gpio19",
"gpio20",
"gpio21",
"gpio22",
"gpio23",
"gpio24",
"gpio25",
"gpio26",
"gpio27",
"gpio28",
"gpio29",
"gpio30",
"gpio31",
"gpio32",
"gpio33",
"gpio34",
"gpio35",
"gpio36",
"gpio37",
"gpio38",
"gpio39",
"gpio40",
"gpio41",
"gpio42",
"gpio43",
"gpio44",
"gpio45",
"gpio46",
"gpio47",
"gpio48",
"gpio49",
"gpio50",
"gpio51",
"gpio52",
"gpio53",
};
enum bcm2835_fsel {
BCM2835_FSEL_GPIO_IN = 0,
BCM2835_FSEL_GPIO_OUT = 1,
BCM2835_FSEL_ALT0 = 4,
BCM2835_FSEL_ALT1 = 5,
BCM2835_FSEL_ALT2 = 6,
BCM2835_FSEL_ALT3 = 7,
BCM2835_FSEL_ALT4 = 3,
BCM2835_FSEL_ALT5 = 2,
BCM2835_FSEL_COUNT = 8,
BCM2835_FSEL_MASK = 0x7,
};
static const char * const bcm2835_functions[BCM2835_FSEL_COUNT] = {
[BCM2835_FSEL_GPIO_IN] = "gpio_in",
[BCM2835_FSEL_GPIO_OUT] = "gpio_out",
[BCM2835_FSEL_ALT0] = "alt0",
[BCM2835_FSEL_ALT1] = "alt1",
[BCM2835_FSEL_ALT2] = "alt2",
[BCM2835_FSEL_ALT3] = "alt3",
[BCM2835_FSEL_ALT4] = "alt4",
[BCM2835_FSEL_ALT5] = "alt5",
};
static const char * const irq_type_names[] = {
[IRQ_TYPE_NONE] = "none",
[IRQ_TYPE_EDGE_RISING] = "edge-rising",
[IRQ_TYPE_EDGE_FALLING] = "edge-falling",
[IRQ_TYPE_EDGE_BOTH] = "edge-both",
[IRQ_TYPE_LEVEL_HIGH] = "level-high",
[IRQ_TYPE_LEVEL_LOW] = "level-low",
};
static inline u32 bcm2835_gpio_rd(struct bcm2835_pinctrl *pc, unsigned reg)
{
return readl(pc->base + reg);
}
static inline void bcm2835_gpio_wr(struct bcm2835_pinctrl *pc, unsigned reg,
u32 val)
{
writel(val, pc->base + reg);
}
static inline int bcm2835_gpio_get_bit(struct bcm2835_pinctrl *pc, unsigned reg,
unsigned bit)
{
reg += GPIO_REG_OFFSET(bit) * 4;
return (bcm2835_gpio_rd(pc, reg) >> GPIO_REG_SHIFT(bit)) & 1;
}
/* note NOT a read/modify/write cycle */
static inline void bcm2835_gpio_set_bit(struct bcm2835_pinctrl *pc,
unsigned reg, unsigned bit)
{
reg += GPIO_REG_OFFSET(bit) * 4;
bcm2835_gpio_wr(pc, reg, BIT(GPIO_REG_SHIFT(bit)));
}
static inline enum bcm2835_fsel bcm2835_pinctrl_fsel_get(
struct bcm2835_pinctrl *pc, unsigned pin)
{
u32 val = bcm2835_gpio_rd(pc, FSEL_REG(pin));
enum bcm2835_fsel status = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK;
dev_dbg(pc->dev, "get %08x (%u => %s)\n", val, pin,
bcm2835_functions[status]);
return status;
}
static inline void bcm2835_pinctrl_fsel_set(
struct bcm2835_pinctrl *pc, unsigned pin,
enum bcm2835_fsel fsel)
{
u32 val = bcm2835_gpio_rd(pc, FSEL_REG(pin));
enum bcm2835_fsel cur = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK;
dev_dbg(pc->dev, "read %08x (%u => %s)\n", val, pin,
bcm2835_functions[cur]);
if (cur == fsel)
return;
if (cur != BCM2835_FSEL_GPIO_IN && fsel != BCM2835_FSEL_GPIO_IN) {
/* always transition through GPIO_IN */
val &= ~(BCM2835_FSEL_MASK << FSEL_SHIFT(pin));
val |= BCM2835_FSEL_GPIO_IN << FSEL_SHIFT(pin);
dev_dbg(pc->dev, "trans %08x (%u <= %s)\n", val, pin,
bcm2835_functions[BCM2835_FSEL_GPIO_IN]);
bcm2835_gpio_wr(pc, FSEL_REG(pin), val);
}
val &= ~(BCM2835_FSEL_MASK << FSEL_SHIFT(pin));
val |= fsel << FSEL_SHIFT(pin);
dev_dbg(pc->dev, "write %08x (%u <= %s)\n", val, pin,
bcm2835_functions[fsel]);
bcm2835_gpio_wr(pc, FSEL_REG(pin), val);
}
static int bcm2835_gpio_request(struct gpio_chip *chip, unsigned offset)
{
return pinctrl_request_gpio(chip->base + offset);
}
static void bcm2835_gpio_free(struct gpio_chip *chip, unsigned offset)
{
pinctrl_free_gpio(chip->base + offset);
}
static int bcm2835_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
return pinctrl_gpio_direction_input(chip->base + offset);
}
static int bcm2835_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
return bcm2835_gpio_get_bit(pc, GPLEV0, offset);
}
static int bcm2835_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
return pinctrl_gpio_direction_output(chip->base + offset);
}
static void bcm2835_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
bcm2835_gpio_set_bit(pc, value ? GPSET0 : GPCLR0, offset);
}
static int bcm2835_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
return irq_linear_revmap(pc->irq_domain, offset);
}
static struct gpio_chip bcm2835_gpio_chip __devinitconst = {
.label = MODULE_NAME,
.owner = THIS_MODULE,
.request = bcm2835_gpio_request,
.free = bcm2835_gpio_free,
.direction_input = bcm2835_gpio_direction_input,
.direction_output = bcm2835_gpio_direction_output,
.get = bcm2835_gpio_get,
.set = bcm2835_gpio_set,
.to_irq = bcm2835_gpio_to_irq,
.base = -1,
.ngpio = BCM2835_NUM_GPIOS,
.can_sleep = 0,
};
static irqreturn_t bcm2835_gpio_irq_handler(int irq, void *dev_id)
{
struct bcm2835_gpio_irqdata *irqdata = dev_id;
struct bcm2835_pinctrl *pc = irqdata->pc;
int bank = irqdata->bank;
unsigned long events;
unsigned offset;
unsigned gpio;
unsigned int type;
events = bcm2835_gpio_rd(pc, GPEDS0 + bank * 4);
events &= pc->enabled_irq_map[bank];
for_each_set_bit(offset, &events, 32) {
gpio = (32 * bank) + offset;
type = pc->irq_type[gpio];
/* ack edge triggered IRQs immediately */
if (!(type & IRQ_TYPE_LEVEL_MASK))
bcm2835_gpio_set_bit(pc, GPEDS0, gpio);
generic_handle_irq(irq_linear_revmap(pc->irq_domain, gpio));
/* ack level triggered IRQ after handling them */
if (type & IRQ_TYPE_LEVEL_MASK)
bcm2835_gpio_set_bit(pc, GPEDS0, gpio);
}
return events ? IRQ_HANDLED : IRQ_NONE;
}
static inline void __bcm2835_gpio_irq_config(struct bcm2835_pinctrl *pc,
unsigned reg, unsigned offset, bool enable)
{
u32 value;
reg += GPIO_REG_OFFSET(offset) * 4;
value = bcm2835_gpio_rd(pc, reg);
if (enable)
value |= BIT(GPIO_REG_SHIFT(offset));
else
value &= ~(BIT(GPIO_REG_SHIFT(offset)));
bcm2835_gpio_wr(pc, reg, value);
}
/* fast path for IRQ handler */
static void bcm2835_gpio_irq_config(struct bcm2835_pinctrl *pc,
unsigned offset, bool enable)
{
switch (pc->irq_type[offset]) {
case IRQ_TYPE_EDGE_RISING:
__bcm2835_gpio_irq_config(pc, GPREN0, offset, enable);
break;
case IRQ_TYPE_EDGE_FALLING:
__bcm2835_gpio_irq_config(pc, GPFEN0, offset, enable);
break;
case IRQ_TYPE_EDGE_BOTH:
__bcm2835_gpio_irq_config(pc, GPREN0, offset, enable);
__bcm2835_gpio_irq_config(pc, GPFEN0, offset, enable);
break;
case IRQ_TYPE_LEVEL_HIGH:
__bcm2835_gpio_irq_config(pc, GPHEN0, offset, enable);
break;
case IRQ_TYPE_LEVEL_LOW:
__bcm2835_gpio_irq_config(pc, GPLEN0, offset, enable);
break;
}
}
static void bcm2835_gpio_irq_enable(struct irq_data *data)
{
struct bcm2835_pinctrl *pc = irq_data_get_irq_chip_data(data);
unsigned gpio = irqd_to_hwirq(data);
unsigned offset = GPIO_REG_SHIFT(gpio);
unsigned bank = GPIO_REG_OFFSET(gpio);
unsigned long flags;
spin_lock_irqsave(&pc->irq_lock[bank], flags);
set_bit(offset, &pc->enabled_irq_map[bank]);
bcm2835_gpio_irq_config(pc, gpio, true);
spin_unlock_irqrestore(&pc->irq_lock[bank], flags);
}
static void bcm2835_gpio_irq_disable(struct irq_data *data)
{
struct bcm2835_pinctrl *pc = irq_data_get_irq_chip_data(data);
unsigned gpio = irqd_to_hwirq(data);
unsigned offset = GPIO_REG_SHIFT(gpio);
unsigned bank = GPIO_REG_OFFSET(gpio);
unsigned long flags;
spin_lock_irqsave(&pc->irq_lock[bank], flags);
bcm2835_gpio_irq_config(pc, gpio, false);
clear_bit(offset, &pc->enabled_irq_map[bank]);
spin_unlock_irqrestore(&pc->irq_lock[bank], flags);
}
static int __bcm2835_gpio_irq_set_type_disabled(struct bcm2835_pinctrl *pc,
unsigned offset, unsigned int type)
{
switch (type) {
case IRQ_TYPE_NONE:
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_EDGE_BOTH:
case IRQ_TYPE_LEVEL_HIGH:
case IRQ_TYPE_LEVEL_LOW:
pc->irq_type[offset] = type;
break;
default:
return -EINVAL;
}
return 0;
}
/* slower path for reconfiguring IRQ type */
static int __bcm2835_gpio_irq_set_type_enabled(struct bcm2835_pinctrl *pc,
unsigned offset, unsigned int type)
{
switch (type) {
case IRQ_TYPE_NONE:
if (pc->irq_type[offset] != type) {
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
}
break;
case IRQ_TYPE_EDGE_RISING:
if (pc->irq_type[offset] == IRQ_TYPE_EDGE_BOTH) {
/* RISING already enabled, disable FALLING */
pc->irq_type[offset] = IRQ_TYPE_EDGE_FALLING;
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
} else if (pc->irq_type[offset] != type) {
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
bcm2835_gpio_irq_config(pc, offset, true);
}
break;
case IRQ_TYPE_EDGE_FALLING:
if (pc->irq_type[offset] == IRQ_TYPE_EDGE_BOTH) {
/* FALLING already enabled, disable RISING */
pc->irq_type[offset] = IRQ_TYPE_EDGE_RISING;
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
} else if (pc->irq_type[offset] != type) {
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
bcm2835_gpio_irq_config(pc, offset, true);
}
break;
case IRQ_TYPE_EDGE_BOTH:
if (pc->irq_type[offset] == IRQ_TYPE_EDGE_RISING) {
/* RISING already enabled, enable FALLING too */
pc->irq_type[offset] = IRQ_TYPE_EDGE_FALLING;
bcm2835_gpio_irq_config(pc, offset, true);
pc->irq_type[offset] = type;
} else if (pc->irq_type[offset] == IRQ_TYPE_EDGE_FALLING) {
/* FALLING already enabled, enable RISING too */
pc->irq_type[offset] = IRQ_TYPE_EDGE_RISING;
bcm2835_gpio_irq_config(pc, offset, true);
pc->irq_type[offset] = type;
} else if (pc->irq_type[offset] != type) {
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
bcm2835_gpio_irq_config(pc, offset, true);
}
break;
case IRQ_TYPE_LEVEL_HIGH:
case IRQ_TYPE_LEVEL_LOW:
if (pc->irq_type[offset] != type) {
bcm2835_gpio_irq_config(pc, offset, false);
pc->irq_type[offset] = type;
bcm2835_gpio_irq_config(pc, offset, true);
}
break;
default:
return -EINVAL;
}
return 0;
}
static int bcm2835_gpio_irq_set_type(struct irq_data *data, unsigned int type)
{
struct bcm2835_pinctrl *pc = irq_data_get_irq_chip_data(data);
unsigned gpio = irqd_to_hwirq(data);
unsigned offset = GPIO_REG_SHIFT(gpio);
unsigned bank = GPIO_REG_OFFSET(gpio);
unsigned long flags;
int ret;
spin_lock_irqsave(&pc->irq_lock[bank], flags);
if (test_bit(offset, &pc->enabled_irq_map[bank]))
ret = __bcm2835_gpio_irq_set_type_enabled(pc, gpio, type);
else
ret = __bcm2835_gpio_irq_set_type_disabled(pc, gpio, type);
spin_unlock_irqrestore(&pc->irq_lock[bank], flags);
return ret;
}
static struct irq_chip bcm2835_gpio_irq_chip = {
.name = MODULE_NAME,
.irq_enable = bcm2835_gpio_irq_enable,
.irq_disable = bcm2835_gpio_irq_disable,
.irq_set_type = bcm2835_gpio_irq_set_type,
};
static int bcm2835_pctl_get_groups_count(struct pinctrl_dev *pctldev)
{
return ARRAY_SIZE(bcm2835_gpio_groups);
}
static const char *bcm2835_pctl_get_group_name(struct pinctrl_dev *pctldev,
unsigned selector)
{
return bcm2835_gpio_groups[selector];
}
static int bcm2835_pctl_get_group_pins(struct pinctrl_dev *pctldev,
unsigned selector,
const unsigned **pins,
unsigned *num_pins)
{
*pins = &bcm2835_gpio_pins[selector].number;
*num_pins = 1;
return 0;
}
static void bcm2835_pctl_pin_dbg_show(struct pinctrl_dev *pctldev,
struct seq_file *s,
unsigned offset)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
enum bcm2835_fsel fsel = bcm2835_pinctrl_fsel_get(pc, offset);
const char *fname = bcm2835_functions[fsel];
int value = bcm2835_gpio_get_bit(pc, GPLEV0, offset);
int irq = irq_find_mapping(pc->irq_domain, offset);
seq_printf(s, "function %s in %s; irq %d (%s)",
fname, value ? "hi" : "lo",
irq, irq_type_names[pc->irq_type[offset]]);
}
static void bcm2835_pctl_dt_free_map(struct pinctrl_dev *pctldev,
struct pinctrl_map *maps, unsigned num_maps)
{
int i;
for (i = 0; i < num_maps; i++)
if (maps[i].type == PIN_MAP_TYPE_CONFIGS_PIN)
kfree(maps[i].data.configs.configs);
kfree(maps);
}
static int bcm2835_pctl_dt_node_to_map_func(struct bcm2835_pinctrl *pc,
struct device_node *np, u32 pin, u32 fnum,
struct pinctrl_map **maps)
{
struct pinctrl_map *map = *maps;
if (fnum >= ARRAY_SIZE(bcm2835_functions)) {
dev_err(pc->dev, "%s: invalid brcm,function %d\n",
of_node_full_name(np), fnum);
return -EINVAL;
}
map->type = PIN_MAP_TYPE_MUX_GROUP;
map->data.mux.group = bcm2835_gpio_groups[pin];
map->data.mux.function = bcm2835_functions[fnum];
(*maps)++;
return 0;
}
static int bcm2835_pctl_dt_node_to_map_pull(struct bcm2835_pinctrl *pc,
struct device_node *np, u32 pin, u32 pull,
struct pinctrl_map **maps)
{
struct pinctrl_map *map = *maps;
unsigned long *configs;
if (pull > 2) {
dev_err(pc->dev, "%s: invalid brcm,pull %d\n",
of_node_full_name(np), pull);
return -EINVAL;
}
configs = kzalloc(sizeof(*configs), GFP_KERNEL);
if (!configs)
return -ENOMEM;
configs[0] = BCM2835_PINCONF_PACK(BCM2835_PINCONF_PARAM_PULL, pull);
map->type = PIN_MAP_TYPE_CONFIGS_PIN;
map->data.configs.group_or_pin = bcm2835_gpio_pins[pin].name;
map->data.configs.configs = configs;
map->data.configs.num_configs = 1;
(*maps)++;
return 0;
}
static inline u32 prop_u32(struct property *p, int i)
{
return be32_to_cpup(((__be32 *)p->value) + i);
}
static int bcm2835_pctl_dt_node_to_map(struct pinctrl_dev *pctldev,
struct device_node *np,
struct pinctrl_map **map, unsigned *num_maps)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
struct property *pins, *funcs, *pulls;
int num_pins, num_funcs, num_pulls, maps_per_pin;
struct pinctrl_map *maps, *cur_map;
int i, err;
u32 pin, func, pull;
pins = of_find_property(np, "brcm,pins", NULL);
if (!pins) {
dev_err(pc->dev, "%s: missing brcm,pins property\n",
of_node_full_name(np));
return -EINVAL;
}
funcs = of_find_property(np, "brcm,function", NULL);
pulls = of_find_property(np, "brcm,pull", NULL);
if (!funcs && !pulls) {
dev_err(pc->dev,
"%s: neither brcm,function nor brcm,pull specified\n",
of_node_full_name(np));
return -EINVAL;
}
num_pins = pins->length / 4;
num_funcs = funcs ? (funcs->length / 4) : 0;
num_pulls = pulls ? (pulls->length / 4) : 0;
if (num_funcs > 1 && num_funcs != num_pins) {
dev_err(pc->dev,
"%s: brcm,function must have 1 or %d entries\n",
of_node_full_name(np), num_pins);
return -EINVAL;
}
if (num_pulls > 1 && num_pulls != num_pins) {
dev_err(pc->dev,
"%s: brcm,pull must have 1 or %d entries\n",
of_node_full_name(np), num_pins);
return -EINVAL;
}
maps_per_pin = 0;
if (num_funcs)
maps_per_pin++;
if (num_pulls)
maps_per_pin++;
cur_map = maps = kzalloc(num_pins * maps_per_pin * sizeof(*maps),
GFP_KERNEL);
if (!maps)
return -ENOMEM;
for (i = 0; i < num_pins; i++) {
pin = prop_u32(pins, i);
if (pin >= ARRAY_SIZE(bcm2835_gpio_pins)) {
dev_err(pc->dev, "%s: invalid brcm,pins value %d\n",
of_node_full_name(np), pin);
err = -EINVAL;
goto out;
}
if (num_funcs) {
func = prop_u32(funcs, (num_funcs > 1) ? i : 0);
err = bcm2835_pctl_dt_node_to_map_func(pc, np, pin,
func, &cur_map);
if (err)
goto out;
}
if (num_pulls) {
pull = prop_u32(pulls, (num_pulls > 1) ? i : 0);
err = bcm2835_pctl_dt_node_to_map_pull(pc, np, pin,
pull, &cur_map);
if (err)
goto out;
}
}
*map = maps;
*num_maps = num_pins * maps_per_pin;
return 0;
out:
kfree(maps);
return err;
}
static struct pinctrl_ops bcm2835_pctl_ops = {
.get_groups_count = bcm2835_pctl_get_groups_count,
.get_group_name = bcm2835_pctl_get_group_name,
.get_group_pins = bcm2835_pctl_get_group_pins,
.pin_dbg_show = bcm2835_pctl_pin_dbg_show,
.dt_node_to_map = bcm2835_pctl_dt_node_to_map,
.dt_free_map = bcm2835_pctl_dt_free_map,
};
static int bcm2835_pmx_get_functions_count(struct pinctrl_dev *pctldev)
{
return BCM2835_FSEL_COUNT;
}
static const char *bcm2835_pmx_get_function_name(struct pinctrl_dev *pctldev,
unsigned selector)
{
return bcm2835_functions[selector];
}
static int bcm2835_pmx_get_function_groups(struct pinctrl_dev *pctldev,
unsigned selector,
const char * const **groups,
unsigned * const num_groups)
{
/* every pin can do every function */
*groups = bcm2835_gpio_groups;
*num_groups = ARRAY_SIZE(bcm2835_gpio_groups);
return 0;
}
static int bcm2835_pmx_enable(struct pinctrl_dev *pctldev,
unsigned func_selector,
unsigned group_selector)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
bcm2835_pinctrl_fsel_set(pc, group_selector, func_selector);
return 0;
}
static void bcm2835_pmx_disable(struct pinctrl_dev *pctldev,
unsigned func_selector,
unsigned group_selector)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
/* disable by setting to GPIO_IN */
bcm2835_pinctrl_fsel_set(pc, group_selector, BCM2835_FSEL_GPIO_IN);
}
static void bcm2835_pmx_gpio_disable_free(struct pinctrl_dev *pctldev,
struct pinctrl_gpio_range *range,
unsigned offset)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
/* disable by setting to GPIO_IN */
bcm2835_pinctrl_fsel_set(pc, offset, BCM2835_FSEL_GPIO_IN);
}
static int bcm2835_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
struct pinctrl_gpio_range *range,
unsigned offset,
bool input)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
enum bcm2835_fsel fsel = input ?
BCM2835_FSEL_GPIO_IN : BCM2835_FSEL_GPIO_OUT;
bcm2835_pinctrl_fsel_set(pc, offset, fsel);
return 0;
}
static struct pinmux_ops bcm2835_pmx_ops = {
.get_functions_count = bcm2835_pmx_get_functions_count,
.get_function_name = bcm2835_pmx_get_function_name,
.get_function_groups = bcm2835_pmx_get_function_groups,
.enable = bcm2835_pmx_enable,
.disable = bcm2835_pmx_disable,
.gpio_disable_free = bcm2835_pmx_gpio_disable_free,
.gpio_set_direction = bcm2835_pmx_gpio_set_direction,
};
static int bcm2835_pinconf_get(struct pinctrl_dev *pctldev,
unsigned pin, unsigned long *config)
{
/* No way to read back config in HW */
return -ENOTSUPP;
}
static int bcm2835_pinconf_set(struct pinctrl_dev *pctldev,
unsigned pin, unsigned long config)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
enum bcm2835_pinconf_param param = BCM2835_PINCONF_UNPACK_PARAM(config);
u16 arg = BCM2835_PINCONF_UNPACK_ARG(config);
u32 off, bit;
if (param != BCM2835_PINCONF_PARAM_PULL)
return -EINVAL;
off = GPIO_REG_OFFSET(pin);
bit = GPIO_REG_SHIFT(pin);
bcm2835_gpio_wr(pc, GPPUD, arg & 3);
/*
* Docs say to wait 150 cycles, but not of what. We assume a
* 1 MHz clock here, which is pretty slow...
*/
udelay(150);
bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), BIT(bit));
udelay(150);
bcm2835_gpio_wr(pc, GPPUDCLK0 + (off * 4), 0);
return 0;
}
struct pinconf_ops bcm2835_pinconf_ops = {
.pin_config_get = bcm2835_pinconf_get,
.pin_config_set = bcm2835_pinconf_set,
};
static struct pinctrl_desc bcm2835_pinctrl_desc = {
.name = MODULE_NAME,
.pins = bcm2835_gpio_pins,
.npins = ARRAY_SIZE(bcm2835_gpio_pins),
.pctlops = &bcm2835_pctl_ops,
.pmxops = &bcm2835_pmx_ops,
.confops = &bcm2835_pinconf_ops,
.owner = THIS_MODULE,
};
static struct pinctrl_gpio_range bcm2835_pinctrl_gpio_range __devinitconst = {
.name = MODULE_NAME,
.npins = BCM2835_NUM_GPIOS,
};
static int __devinit bcm2835_pinctrl_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct bcm2835_pinctrl *pc;
struct resource iomem;
int err, i;
BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_pins) != BCM2835_NUM_GPIOS);
BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_groups) != BCM2835_NUM_GPIOS);
pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL);
if (!pc)
return -ENOMEM;
platform_set_drvdata(pdev, pc);
pc->dev = dev;
err = of_address_to_resource(np, 0, &iomem);
if (err) {
dev_err(dev, "could not get IO memory\n");
return err;
}
pc->base = devm_request_and_ioremap(&pdev->dev, &iomem);
if (!pc->base)
return -EADDRNOTAVAIL;
pc->gpio_chip = bcm2835_gpio_chip;
pc->gpio_chip.dev = dev;
pc->gpio_chip.of_node = np;
pc->irq_domain = irq_domain_add_linear(np, BCM2835_NUM_GPIOS,
&irq_domain_simple_ops, NULL);
if (!pc->irq_domain) {
dev_err(dev, "could not create IRQ domain\n");
return -ENOMEM;
}
for (i = 0; i < BCM2835_NUM_GPIOS; i++) {
int irq = irq_create_mapping(pc->irq_domain, i);
irq_set_lockdep_class(irq, &gpio_lock_class);
irq_set_chip_and_handler(irq, &bcm2835_gpio_irq_chip,
handle_simple_irq);
irq_set_chip_data(irq, pc);
set_irq_flags(irq, IRQF_VALID);
}
for (i = 0; i < BCM2835_NUM_BANKS; i++) {
unsigned long events;
unsigned offset;
int len;
char *name;
/* clear event detection flags */
bcm2835_gpio_wr(pc, GPREN0 + i * 4, 0);
bcm2835_gpio_wr(pc, GPFEN0 + i * 4, 0);
bcm2835_gpio_wr(pc, GPHEN0 + i * 4, 0);
bcm2835_gpio_wr(pc, GPLEN0 + i * 4, 0);
bcm2835_gpio_wr(pc, GPAREN0 + i * 4, 0);
bcm2835_gpio_wr(pc, GPAFEN0 + i * 4, 0);
/* clear all the events */
events = bcm2835_gpio_rd(pc, GPEDS0 + i * 4);
for_each_set_bit(offset, &events, 32)
bcm2835_gpio_wr(pc, GPEDS0 + i * 4, BIT(offset));
pc->irq[i] = irq_of_parse_and_map(np, i);
pc->irq_data[i].pc = pc;
pc->irq_data[i].bank = i;
spin_lock_init(&pc->irq_lock[i]);
len = strlen(dev_name(pc->dev)) + 16;
name = devm_kzalloc(pc->dev, len, GFP_KERNEL);
if (!name)
return -ENOMEM;
snprintf(name, len, "%s:bank%d", dev_name(pc->dev), i);
err = devm_request_irq(dev, pc->irq[i],
bcm2835_gpio_irq_handler, IRQF_SHARED,
name, &pc->irq_data[i]);
if (err) {
dev_err(dev, "unable to request IRQ %d\n", pc->irq[i]);
return err;
}
}
err = gpiochip_add(&pc->gpio_chip);
if (err) {
dev_err(dev, "could not add GPIO chip\n");
return err;
}
pc->pctl_dev = pinctrl_register(&bcm2835_pinctrl_desc, dev, pc);
if (!pc->pctl_dev) {
gpiochip_remove(&pc->gpio_chip);
return PTR_ERR(pc->pctl_dev);
}
pc->gpio_range = bcm2835_pinctrl_gpio_range;
pc->gpio_range.base = pc->gpio_chip.base;
pc->gpio_range.gc = &pc->gpio_chip;
pinctrl_add_gpio_range(pc->pctl_dev, &pc->gpio_range);
return 0;
}
static int __devexit bcm2835_pinctrl_remove(struct platform_device *pdev)
{
struct bcm2835_pinctrl *pc = platform_get_drvdata(pdev);
pinctrl_unregister(pc->pctl_dev);
gpiochip_remove(&pc->gpio_chip);
return 0;
}
static struct of_device_id bcm2835_pinctrl_match[] __devinitconst = {
{ .compatible = "brcm,bcm2835-gpio" },
{}
};
MODULE_DEVICE_TABLE(of, bcm2835_pinctrl_match);
static struct platform_driver bcm2835_pinctrl_driver = {
.probe = bcm2835_pinctrl_probe,
.remove = bcm2835_pinctrl_remove,
.driver = {
.name = MODULE_NAME,
.owner = THIS_MODULE,
.of_match_table = bcm2835_pinctrl_match,
},
};
module_platform_driver(bcm2835_pinctrl_driver);
MODULE_AUTHOR("Chris Boot, Simon Arlott, Stephen Warren");
MODULE_DESCRIPTION("BCM2835 Pin control driver");
MODULE_LICENSE("GPL");
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