linux/drivers/gpio/gpio-davinci.c
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00

630 lines
16 KiB
C

/*
* TI DaVinci GPIO Support
*
* Copyright (c) 2006-2007 David Brownell
* Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
*
* 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.
*/
#include <linux/gpio.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/platform_data/gpio-davinci.h>
#include <linux/irqchip/chained_irq.h>
struct davinci_gpio_regs {
u32 dir;
u32 out_data;
u32 set_data;
u32 clr_data;
u32 in_data;
u32 set_rising;
u32 clr_rising;
u32 set_falling;
u32 clr_falling;
u32 intstat;
};
typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
#define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
#define chip2controller(chip) \
container_of(chip, struct davinci_gpio_controller, chip)
static void __iomem *gpio_base;
static struct davinci_gpio_regs __iomem *gpio2regs(unsigned gpio)
{
void __iomem *ptr;
if (gpio < 32 * 1)
ptr = gpio_base + 0x10;
else if (gpio < 32 * 2)
ptr = gpio_base + 0x38;
else if (gpio < 32 * 3)
ptr = gpio_base + 0x60;
else if (gpio < 32 * 4)
ptr = gpio_base + 0x88;
else if (gpio < 32 * 5)
ptr = gpio_base + 0xb0;
else
ptr = NULL;
return ptr;
}
static inline struct davinci_gpio_regs __iomem *irq2regs(int irq)
{
struct davinci_gpio_regs __iomem *g;
g = (__force struct davinci_gpio_regs __iomem *)irq_get_chip_data(irq);
return g;
}
static int davinci_gpio_irq_setup(struct platform_device *pdev);
/*--------------------------------------------------------------------------*/
/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
static inline int __davinci_direction(struct gpio_chip *chip,
unsigned offset, bool out, int value)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
unsigned long flags;
u32 temp;
u32 mask = 1 << offset;
spin_lock_irqsave(&d->lock, flags);
temp = readl_relaxed(&g->dir);
if (out) {
temp &= ~mask;
writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
} else {
temp |= mask;
}
writel_relaxed(temp, &g->dir);
spin_unlock_irqrestore(&d->lock, flags);
return 0;
}
static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
{
return __davinci_direction(chip, offset, false, 0);
}
static int
davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
{
return __davinci_direction(chip, offset, true, value);
}
/*
* Read the pin's value (works even if it's set up as output);
* returns zero/nonzero.
*
* Note that changes are synched to the GPIO clock, so reading values back
* right after you've set them may give old values.
*/
static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
return (1 << offset) & readl_relaxed(&g->in_data);
}
/*
* Assuming the pin is muxed as a gpio output, set its output value.
*/
static void
davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
writel_relaxed((1 << offset), value ? &g->set_data : &g->clr_data);
}
static struct davinci_gpio_platform_data *
davinci_gpio_get_pdata(struct platform_device *pdev)
{
struct device_node *dn = pdev->dev.of_node;
struct davinci_gpio_platform_data *pdata;
int ret;
u32 val;
if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
return pdev->dev.platform_data;
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return NULL;
ret = of_property_read_u32(dn, "ti,ngpio", &val);
if (ret)
goto of_err;
pdata->ngpio = val;
ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
if (ret)
goto of_err;
pdata->gpio_unbanked = val;
return pdata;
of_err:
dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
return NULL;
}
#ifdef CONFIG_OF_GPIO
static int davinci_gpio_of_xlate(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec,
u32 *flags)
{
struct davinci_gpio_controller *chips = dev_get_drvdata(gc->dev);
struct davinci_gpio_platform_data *pdata = dev_get_platdata(gc->dev);
if (gpiospec->args[0] > pdata->ngpio)
return -EINVAL;
if (gc != &chips[gpiospec->args[0] / 32].chip)
return -EINVAL;
if (flags)
*flags = gpiospec->args[1];
return gpiospec->args[0] % 32;
}
#endif
static int davinci_gpio_probe(struct platform_device *pdev)
{
int i, base;
unsigned ngpio;
struct davinci_gpio_controller *chips;
struct davinci_gpio_platform_data *pdata;
struct davinci_gpio_regs __iomem *regs;
struct device *dev = &pdev->dev;
struct resource *res;
pdata = davinci_gpio_get_pdata(pdev);
if (!pdata) {
dev_err(dev, "No platform data found\n");
return -EINVAL;
}
dev->platform_data = pdata;
/*
* The gpio banks conceptually expose a segmented bitmap,
* and "ngpio" is one more than the largest zero-based
* bit index that's valid.
*/
ngpio = pdata->ngpio;
if (ngpio == 0) {
dev_err(dev, "How many GPIOs?\n");
return -EINVAL;
}
if (WARN_ON(ARCH_NR_GPIOS < ngpio))
ngpio = ARCH_NR_GPIOS;
chips = devm_kzalloc(dev,
ngpio * sizeof(struct davinci_gpio_controller),
GFP_KERNEL);
if (!chips)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
gpio_base = devm_ioremap_resource(dev, res);
if (IS_ERR(gpio_base))
return PTR_ERR(gpio_base);
for (i = 0, base = 0; base < ngpio; i++, base += 32) {
chips[i].chip.label = "DaVinci";
chips[i].chip.direction_input = davinci_direction_in;
chips[i].chip.get = davinci_gpio_get;
chips[i].chip.direction_output = davinci_direction_out;
chips[i].chip.set = davinci_gpio_set;
chips[i].chip.base = base;
chips[i].chip.ngpio = ngpio - base;
if (chips[i].chip.ngpio > 32)
chips[i].chip.ngpio = 32;
#ifdef CONFIG_OF_GPIO
chips[i].chip.of_gpio_n_cells = 2;
chips[i].chip.of_xlate = davinci_gpio_of_xlate;
chips[i].chip.dev = dev;
chips[i].chip.of_node = dev->of_node;
#endif
spin_lock_init(&chips[i].lock);
regs = gpio2regs(base);
chips[i].regs = regs;
chips[i].set_data = &regs->set_data;
chips[i].clr_data = &regs->clr_data;
chips[i].in_data = &regs->in_data;
gpiochip_add(&chips[i].chip);
}
platform_set_drvdata(pdev, chips);
davinci_gpio_irq_setup(pdev);
return 0;
}
/*--------------------------------------------------------------------------*/
/*
* We expect irqs will normally be set up as input pins, but they can also be
* used as output pins ... which is convenient for testing.
*
* NOTE: The first few GPIOs also have direct INTC hookups in addition
* to their GPIOBNK0 irq, with a bit less overhead.
*
* All those INTC hookups (direct, plus several IRQ banks) can also
* serve as EDMA event triggers.
*/
static void gpio_irq_disable(struct irq_data *d)
{
struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
u32 mask = (u32) irq_data_get_irq_handler_data(d);
writel_relaxed(mask, &g->clr_falling);
writel_relaxed(mask, &g->clr_rising);
}
static void gpio_irq_enable(struct irq_data *d)
{
struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
u32 mask = (u32) irq_data_get_irq_handler_data(d);
unsigned status = irqd_get_trigger_type(d);
status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
if (!status)
status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
if (status & IRQ_TYPE_EDGE_FALLING)
writel_relaxed(mask, &g->set_falling);
if (status & IRQ_TYPE_EDGE_RISING)
writel_relaxed(mask, &g->set_rising);
}
static int gpio_irq_type(struct irq_data *d, unsigned trigger)
{
if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
return -EINVAL;
return 0;
}
static struct irq_chip gpio_irqchip = {
.name = "GPIO",
.irq_enable = gpio_irq_enable,
.irq_disable = gpio_irq_disable,
.irq_set_type = gpio_irq_type,
.flags = IRQCHIP_SET_TYPE_MASKED,
};
static void
gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct davinci_gpio_regs __iomem *g;
u32 mask = 0xffff;
struct davinci_gpio_controller *d;
d = (struct davinci_gpio_controller *)irq_desc_get_handler_data(desc);
g = (struct davinci_gpio_regs __iomem *)d->regs;
/* we only care about one bank */
if (irq & 1)
mask <<= 16;
/* temporarily mask (level sensitive) parent IRQ */
chained_irq_enter(irq_desc_get_chip(desc), desc);
while (1) {
u32 status;
int bit;
/* ack any irqs */
status = readl_relaxed(&g->intstat) & mask;
if (!status)
break;
writel_relaxed(status, &g->intstat);
/* now demux them to the right lowlevel handler */
while (status) {
bit = __ffs(status);
status &= ~BIT(bit);
generic_handle_irq(
irq_find_mapping(d->irq_domain,
d->chip.base + bit));
}
}
chained_irq_exit(irq_desc_get_chip(desc), desc);
/* now it may re-trigger */
}
static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio_controller *d = chip2controller(chip);
if (d->irq_domain)
return irq_create_mapping(d->irq_domain, d->chip.base + offset);
else
return -ENXIO;
}
static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
{
struct davinci_gpio_controller *d = chip2controller(chip);
/*
* NOTE: we assume for now that only irqs in the first gpio_chip
* can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
*/
if (offset < d->gpio_unbanked)
return d->gpio_irq + offset;
else
return -ENODEV;
}
static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
{
struct davinci_gpio_controller *d;
struct davinci_gpio_regs __iomem *g;
u32 mask;
d = (struct davinci_gpio_controller *)data->handler_data;
g = (struct davinci_gpio_regs __iomem *)d->regs;
mask = __gpio_mask(data->irq - d->gpio_irq);
if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
return -EINVAL;
writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
? &g->set_falling : &g->clr_falling);
writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
? &g->set_rising : &g->clr_rising);
return 0;
}
static int
davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
struct davinci_gpio_regs __iomem *g = gpio2regs(hw);
irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
"davinci_gpio");
irq_set_irq_type(irq, IRQ_TYPE_NONE);
irq_set_chip_data(irq, (__force void *)g);
irq_set_handler_data(irq, (void *)__gpio_mask(hw));
set_irq_flags(irq, IRQF_VALID);
return 0;
}
static const struct irq_domain_ops davinci_gpio_irq_ops = {
.map = davinci_gpio_irq_map,
.xlate = irq_domain_xlate_onetwocell,
};
static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
{
static struct irq_chip_type gpio_unbanked;
gpio_unbanked = *container_of(irq_get_chip(irq),
struct irq_chip_type, chip);
return &gpio_unbanked.chip;
};
static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
{
static struct irq_chip gpio_unbanked;
gpio_unbanked = *irq_get_chip(irq);
return &gpio_unbanked;
};
static const struct of_device_id davinci_gpio_ids[];
/*
* NOTE: for suspend/resume, probably best to make a platform_device with
* suspend_late/resume_resume calls hooking into results of the set_wake()
* calls ... so if no gpios are wakeup events the clock can be disabled,
* with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
* (dm6446) can be set appropriately for GPIOV33 pins.
*/
static int davinci_gpio_irq_setup(struct platform_device *pdev)
{
unsigned gpio, bank;
int irq;
struct clk *clk;
u32 binten = 0;
unsigned ngpio, bank_irq;
struct device *dev = &pdev->dev;
struct resource *res;
struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
struct davinci_gpio_platform_data *pdata = dev->platform_data;
struct davinci_gpio_regs __iomem *g;
struct irq_domain *irq_domain = NULL;
const struct of_device_id *match;
struct irq_chip *irq_chip;
gpio_get_irq_chip_cb_t gpio_get_irq_chip;
/*
* Use davinci_gpio_get_irq_chip by default to handle non DT cases
*/
gpio_get_irq_chip = davinci_gpio_get_irq_chip;
match = of_match_device(of_match_ptr(davinci_gpio_ids),
dev);
if (match)
gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data;
ngpio = pdata->ngpio;
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
dev_err(dev, "Invalid IRQ resource\n");
return -EBUSY;
}
bank_irq = res->start;
if (!bank_irq) {
dev_err(dev, "Invalid IRQ resource\n");
return -ENODEV;
}
clk = devm_clk_get(dev, "gpio");
if (IS_ERR(clk)) {
printk(KERN_ERR "Error %ld getting gpio clock?\n",
PTR_ERR(clk));
return PTR_ERR(clk);
}
clk_prepare_enable(clk);
if (!pdata->gpio_unbanked) {
irq = irq_alloc_descs(-1, 0, ngpio, 0);
if (irq < 0) {
dev_err(dev, "Couldn't allocate IRQ numbers\n");
return irq;
}
irq_domain = irq_domain_add_legacy(NULL, ngpio, irq, 0,
&davinci_gpio_irq_ops,
chips);
if (!irq_domain) {
dev_err(dev, "Couldn't register an IRQ domain\n");
return -ENODEV;
}
}
/*
* Arrange gpio_to_irq() support, handling either direct IRQs or
* banked IRQs. Having GPIOs in the first GPIO bank use direct
* IRQs, while the others use banked IRQs, would need some setup
* tweaks to recognize hardware which can do that.
*/
for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 32) {
chips[bank].chip.to_irq = gpio_to_irq_banked;
chips[bank].irq_domain = irq_domain;
}
/*
* AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
* controller only handling trigger modes. We currently assume no
* IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
*/
if (pdata->gpio_unbanked) {
/* pass "bank 0" GPIO IRQs to AINTC */
chips[0].chip.to_irq = gpio_to_irq_unbanked;
chips[0].gpio_irq = bank_irq;
chips[0].gpio_unbanked = pdata->gpio_unbanked;
binten = BIT(0);
/* AINTC handles mask/unmask; GPIO handles triggering */
irq = bank_irq;
irq_chip = gpio_get_irq_chip(irq);
irq_chip->name = "GPIO-AINTC";
irq_chip->irq_set_type = gpio_irq_type_unbanked;
/* default trigger: both edges */
g = gpio2regs(0);
writel_relaxed(~0, &g->set_falling);
writel_relaxed(~0, &g->set_rising);
/* set the direct IRQs up to use that irqchip */
for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++, irq++) {
irq_set_chip(irq, irq_chip);
irq_set_handler_data(irq, &chips[gpio / 32]);
irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
}
goto done;
}
/*
* Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
* then chain through our own handler.
*/
for (gpio = 0, bank = 0; gpio < ngpio; bank++, bank_irq++, gpio += 16) {
/* disabled by default, enabled only as needed */
g = gpio2regs(gpio);
writel_relaxed(~0, &g->clr_falling);
writel_relaxed(~0, &g->clr_rising);
/* set up all irqs in this bank */
irq_set_chained_handler(bank_irq, gpio_irq_handler);
/*
* Each chip handles 32 gpios, and each irq bank consists of 16
* gpio irqs. Pass the irq bank's corresponding controller to
* the chained irq handler.
*/
irq_set_handler_data(bank_irq, &chips[gpio / 32]);
binten |= BIT(bank);
}
done:
/*
* BINTEN -- per-bank interrupt enable. genirq would also let these
* bits be set/cleared dynamically.
*/
writel_relaxed(binten, gpio_base + BINTEN);
return 0;
}
#if IS_ENABLED(CONFIG_OF)
static const struct of_device_id davinci_gpio_ids[] = {
{ .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
{ .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
#endif
static struct platform_driver davinci_gpio_driver = {
.probe = davinci_gpio_probe,
.driver = {
.name = "davinci_gpio",
.of_match_table = of_match_ptr(davinci_gpio_ids),
},
};
/**
* GPIO driver registration needs to be done before machine_init functions
* access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
*/
static int __init davinci_gpio_drv_reg(void)
{
return platform_driver_register(&davinci_gpio_driver);
}
postcore_initcall(davinci_gpio_drv_reg);