linux/drivers/gpio/gpio-msic.c
Paul Gortmaker 98102880c7 gpio: msic: drop unused MODULE_ tags from non-modular code
The Kconfig currently controlling compilation of this code is:

drivers/gpio/Kconfig:config GPIO_MSIC
drivers/gpio/Kconfig:   bool "Intel MSIC mixed signal gpio support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modular infrastructure use, so that
when reading the driver there is no doubt it is builtin-only.

We delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

We don't replace module.h with init.h since the file already has that.

Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-08-23 11:22:09 +02:00

331 lines
8.3 KiB
C

/*
* Intel Medfield MSIC GPIO driver>
* Copyright (c) 2011, Intel Corporation.
*
* Author: Mathias Nyman <mathias.nyman@linux.intel.com>
* Based on intel_pmic_gpio.c
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/mfd/intel_msic.h>
/* the offset for the mapping of global gpio pin to irq */
#define MSIC_GPIO_IRQ_OFFSET 0x100
#define MSIC_GPIO_DIR_IN 0
#define MSIC_GPIO_DIR_OUT BIT(5)
#define MSIC_GPIO_TRIG_FALL BIT(1)
#define MSIC_GPIO_TRIG_RISE BIT(2)
/* masks for msic gpio output GPIOxxxxCTLO registers */
#define MSIC_GPIO_DIR_MASK BIT(5)
#define MSIC_GPIO_DRV_MASK BIT(4)
#define MSIC_GPIO_REN_MASK BIT(3)
#define MSIC_GPIO_RVAL_MASK (BIT(2) | BIT(1))
#define MSIC_GPIO_DOUT_MASK BIT(0)
/* masks for msic gpio input GPIOxxxxCTLI registers */
#define MSIC_GPIO_GLBYP_MASK BIT(5)
#define MSIC_GPIO_DBNC_MASK (BIT(4) | BIT(3))
#define MSIC_GPIO_INTCNT_MASK (BIT(2) | BIT(1))
#define MSIC_GPIO_DIN_MASK BIT(0)
#define MSIC_NUM_GPIO 24
struct msic_gpio {
struct platform_device *pdev;
struct mutex buslock;
struct gpio_chip chip;
int irq;
unsigned irq_base;
unsigned long trig_change_mask;
unsigned trig_type;
};
/*
* MSIC has 24 gpios, 16 low voltage (1.2-1.8v) and 8 high voltage (3v).
* Both the high and low voltage gpios are divided in two banks.
* GPIOs are numbered with GPIO0LV0 as gpio_base in the following order:
* GPIO0LV0..GPIO0LV7: low voltage, bank 0, gpio_base
* GPIO1LV0..GPIO1LV7: low voltage, bank 1, gpio_base + 8
* GPIO0HV0..GPIO0HV3: high voltage, bank 0, gpio_base + 16
* GPIO1HV0..GPIO1HV3: high voltage, bank 1, gpio_base + 20
*/
static int msic_gpio_to_ireg(unsigned offset)
{
if (offset >= MSIC_NUM_GPIO)
return -EINVAL;
if (offset < 8)
return INTEL_MSIC_GPIO0LV0CTLI - offset;
if (offset < 16)
return INTEL_MSIC_GPIO1LV0CTLI - offset + 8;
if (offset < 20)
return INTEL_MSIC_GPIO0HV0CTLI - offset + 16;
return INTEL_MSIC_GPIO1HV0CTLI - offset + 20;
}
static int msic_gpio_to_oreg(unsigned offset)
{
if (offset >= MSIC_NUM_GPIO)
return -EINVAL;
if (offset < 8)
return INTEL_MSIC_GPIO0LV0CTLO - offset;
if (offset < 16)
return INTEL_MSIC_GPIO1LV0CTLO - offset + 8;
if (offset < 20)
return INTEL_MSIC_GPIO0HV0CTLO - offset + 16;
return INTEL_MSIC_GPIO1HV0CTLO - offset + 20;
}
static int msic_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
int reg;
reg = msic_gpio_to_oreg(offset);
if (reg < 0)
return reg;
return intel_msic_reg_update(reg, MSIC_GPIO_DIR_IN, MSIC_GPIO_DIR_MASK);
}
static int msic_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
int reg;
unsigned mask;
value = (!!value) | MSIC_GPIO_DIR_OUT;
mask = MSIC_GPIO_DIR_MASK | MSIC_GPIO_DOUT_MASK;
reg = msic_gpio_to_oreg(offset);
if (reg < 0)
return reg;
return intel_msic_reg_update(reg, value, mask);
}
static int msic_gpio_get(struct gpio_chip *chip, unsigned offset)
{
u8 r;
int ret;
int reg;
reg = msic_gpio_to_ireg(offset);
if (reg < 0)
return reg;
ret = intel_msic_reg_read(reg, &r);
if (ret < 0)
return ret;
return !!(r & MSIC_GPIO_DIN_MASK);
}
static void msic_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
int reg;
reg = msic_gpio_to_oreg(offset);
if (reg < 0)
return;
intel_msic_reg_update(reg, !!value , MSIC_GPIO_DOUT_MASK);
}
/*
* This is called from genirq with mg->buslock locked and
* irq_desc->lock held. We can not access the scu bus here, so we
* store the change and update in the bus_sync_unlock() function below
*/
static int msic_irq_type(struct irq_data *data, unsigned type)
{
struct msic_gpio *mg = irq_data_get_irq_chip_data(data);
u32 gpio = data->irq - mg->irq_base;
if (gpio >= mg->chip.ngpio)
return -EINVAL;
/* mark for which gpio the trigger changed, protected by buslock */
mg->trig_change_mask |= (1 << gpio);
mg->trig_type = type;
return 0;
}
static int msic_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct msic_gpio *mg = gpiochip_get_data(chip);
return mg->irq_base + offset;
}
static void msic_bus_lock(struct irq_data *data)
{
struct msic_gpio *mg = irq_data_get_irq_chip_data(data);
mutex_lock(&mg->buslock);
}
static void msic_bus_sync_unlock(struct irq_data *data)
{
struct msic_gpio *mg = irq_data_get_irq_chip_data(data);
int offset;
int reg;
u8 trig = 0;
/* We can only get one change at a time as the buslock covers the
entire transaction. The irq_desc->lock is dropped before we are
called but that is fine */
if (mg->trig_change_mask) {
offset = __ffs(mg->trig_change_mask);
reg = msic_gpio_to_ireg(offset);
if (reg < 0)
goto out;
if (mg->trig_type & IRQ_TYPE_EDGE_RISING)
trig |= MSIC_GPIO_TRIG_RISE;
if (mg->trig_type & IRQ_TYPE_EDGE_FALLING)
trig |= MSIC_GPIO_TRIG_FALL;
intel_msic_reg_update(reg, trig, MSIC_GPIO_INTCNT_MASK);
mg->trig_change_mask = 0;
}
out:
mutex_unlock(&mg->buslock);
}
/* Firmware does all the masking and unmasking for us, no masking here. */
static void msic_irq_unmask(struct irq_data *data) { }
static void msic_irq_mask(struct irq_data *data) { }
static struct irq_chip msic_irqchip = {
.name = "MSIC-GPIO",
.irq_mask = msic_irq_mask,
.irq_unmask = msic_irq_unmask,
.irq_set_type = msic_irq_type,
.irq_bus_lock = msic_bus_lock,
.irq_bus_sync_unlock = msic_bus_sync_unlock,
};
static void msic_gpio_irq_handler(struct irq_desc *desc)
{
struct irq_data *data = irq_desc_get_irq_data(desc);
struct msic_gpio *mg = irq_data_get_irq_handler_data(data);
struct irq_chip *chip = irq_data_get_irq_chip(data);
struct intel_msic *msic = pdev_to_intel_msic(mg->pdev);
int i;
int bitnr;
u8 pin;
unsigned long pending = 0;
for (i = 0; i < (mg->chip.ngpio / BITS_PER_BYTE); i++) {
intel_msic_irq_read(msic, INTEL_MSIC_GPIO0LVIRQ + i, &pin);
pending = pin;
if (pending) {
for_each_set_bit(bitnr, &pending, BITS_PER_BYTE)
generic_handle_irq(mg->irq_base +
(i * BITS_PER_BYTE) + bitnr);
}
}
chip->irq_eoi(data);
}
static int platform_msic_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct intel_msic_gpio_pdata *pdata = dev_get_platdata(dev);
struct msic_gpio *mg;
int irq = platform_get_irq(pdev, 0);
int retval;
int i;
if (irq < 0) {
dev_err(dev, "no IRQ line\n");
return -EINVAL;
}
if (!pdata || !pdata->gpio_base) {
dev_err(dev, "incorrect or missing platform data\n");
return -EINVAL;
}
mg = kzalloc(sizeof(*mg), GFP_KERNEL);
if (!mg)
return -ENOMEM;
dev_set_drvdata(dev, mg);
mg->pdev = pdev;
mg->irq = irq;
mg->irq_base = pdata->gpio_base + MSIC_GPIO_IRQ_OFFSET;
mg->chip.label = "msic_gpio";
mg->chip.direction_input = msic_gpio_direction_input;
mg->chip.direction_output = msic_gpio_direction_output;
mg->chip.get = msic_gpio_get;
mg->chip.set = msic_gpio_set;
mg->chip.to_irq = msic_gpio_to_irq;
mg->chip.base = pdata->gpio_base;
mg->chip.ngpio = MSIC_NUM_GPIO;
mg->chip.can_sleep = true;
mg->chip.parent = dev;
mutex_init(&mg->buslock);
retval = gpiochip_add_data(&mg->chip, mg);
if (retval) {
dev_err(dev, "Adding MSIC gpio chip failed\n");
goto err;
}
for (i = 0; i < mg->chip.ngpio; i++) {
irq_set_chip_data(i + mg->irq_base, mg);
irq_set_chip_and_handler(i + mg->irq_base,
&msic_irqchip,
handle_simple_irq);
}
irq_set_chained_handler_and_data(mg->irq, msic_gpio_irq_handler, mg);
return 0;
err:
kfree(mg);
return retval;
}
static struct platform_driver platform_msic_gpio_driver = {
.driver = {
.name = "msic_gpio",
},
.probe = platform_msic_gpio_probe,
};
static int __init platform_msic_gpio_init(void)
{
return platform_driver_register(&platform_msic_gpio_driver);
}
subsys_initcall(platform_msic_gpio_init);