linux_dsm_epyc7002/drivers/pinctrl/pinctrl-msm.c
Linus Torvalds 154d6f18a4 This is the bulk of GPIO changes for v3.15:
- Merged in a branch of irqchip changes from Thomas
   Gleixner: we need to have new callbacks from the
   irqchip to determine if the GPIO line will be eligible
   for IRQs, and this callback must be able to say "no".
   After some thinking I got the branch from tglx and
   have switched all current users over to use this.
 
 - Based on tglx patches, we have added some generic
   irqchip helpers in the gpiolib core. These will
   help centralize code when GPIO drivers have simple
   chained/cascaded IRQs. Drivers will still define
   their irqchip vtables, but the gpiolib core will
   take care of irqdomain set-up, mapping from local
   offsets to Linux irqs, and reserve resources by
   marking the GPIO lines for IRQs.
 
 - Initially the PL061 and Nomadik GPIO/pin control
   drivers have been switched over to use the new
   gpiochip-to-irqchip infrastructure with more
   drivers expected for the next kernel cycle. The
   factoring of just two drivers still makes it worth
   it so it is already a win.
 
 - A new driver for the Synopsys DesignWare APB GPIO
   block.
 
 - Modify the DaVinci GPIO driver to be reusable also
   for the new TI Keystone architecture.
 
 - A new driver for the LSI ZEVIO SoCs.
 
 - Delete the obsolte tnetv107x driver.
 
 - Some incremental work on GPIO descriptors: have
   gpiod_direction_output() use a logical level,
   respecting assertion polarity through ACTIVE_LOW
   flags, adding gpiod_direction_output_raw() for the
   case where you want to set that very value. Add
   gpiochip_get_desc() to fetch a GPIO descriptor from
   a specific offset on a certain chip inside driver
   code.
 
 - Switch ACPI GPIO code over to using
   gpiochip_get_desc() and get rid of gpio_to_desc().
 
 - The ACPI GPIO event handling code has been reworked
   after encountering an actual real life implementation.
 
 - Support for ACPI GPIO operation regions.
 
 - Generic GPIO chips can now be assigned labels/names
   from platform data.
 
 - We now clamp values returned from GPIO drivers to
   the boolean [0,1] range.
 
 - Some improved documentation on how to use the polarity
   flag was added.
 
 - The a large slew of incremental driver updates and
   non-critical fixes. Some targeted for stable.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJTPQnkAAoJEEEQszewGV1zyf4P/AmXV0O/FoyeQnXDxDsp7V/t
 JpfD0Gy8FlFmRxjG+UYutRCWUHxFQJU+j0ToVC4/N8clNS1LwA+ZwhNgB8dqRokz
 JVeeqUPn95z2kGe3j9DgVXWMRAytq7y8fXFuNUN36losceuxyOj4mYKLP9Yjnp9l
 4pS1TtQHF95a7qmnyYjGZy8VNcUz1gJ7wJrGxKI+Kl/8pcdA6rPqom6ozCXpZjaD
 5GGQoSvXKIn44+8qZeJsebd1YEso/8K66e9JomcGEsuZl78ArDOzoSllpYF2h/RM
 bo4BFUmoOL3/jVp7FFVbybfolwuRmQesY4NFqx03e+y++hxHFHl90FT+mnednS2Q
 k4lB0o1YRjf2tfMmm4cJ3tVBnFRhssTVb9ynDbzUw61mNVEuxP90f/njrHlObnPT
 1uVVWUE+4ojral213S2IYGHkg1OlWSn0DP6tEaswjOsGJrMdXpdxS5RPwcRtcByT
 HufZRNbUbLzXBzf4WeV2foSS3XqbXYcuMfdRBSWrbuJqW56robbdKKyvrMRPvh7j
 FV7SEK0yFPRe3nuzKM+t9TDGdUt4qivv/YfVeGfCnTVgFOac6cKrHG9gzM58mVcb
 4czG3B1TbqgfGVeZuew4qUdlHSmnSsS+pf/h9Yh9QCHqaKGh3R17cSDxIKAIVTIW
 pH6nuShTXsbrmRMeMhux
 =8Qqf
 -----END PGP SIGNATURE-----

Merge tag 'gpio-v3.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull bulk of gpio updates from Linus Walleij:
 "A pretty big chunk of changes this time, but it has all been on
  rotation in linux-next and had some testing.  Of course there will be
  some amount of fixes on top...

   - Merged in a branch of irqchip changes from Thomas Gleixner: we need
     to have new callbacks from the irqchip to determine if the GPIO
     line will be eligible for IRQs, and this callback must be able to
     say "no".  After some thinking I got the branch from tglx and have
     switched all current users over to use this.

   - Based on tglx patches, we have added some generic irqchip helpers
     in the gpiolib core.  These will help centralize code when GPIO
     drivers have simple chained/cascaded IRQs.  Drivers will still
     define their irqchip vtables, but the gpiolib core will take care
     of irqdomain set-up, mapping from local offsets to Linux irqs, and
     reserve resources by marking the GPIO lines for IRQs.

   - Initially the PL061 and Nomadik GPIO/pin control drivers have been
     switched over to use the new gpiochip-to-irqchip infrastructure
     with more drivers expected for the next kernel cycle.  The
     factoring of just two drivers still makes it worth it so it is
     already a win.

   - A new driver for the Synopsys DesignWare APB GPIO block.

   - Modify the DaVinci GPIO driver to be reusable also for the new TI
     Keystone architecture.

   - A new driver for the LSI ZEVIO SoCs.

   - Delete the obsolte tnetv107x driver.

   - Some incremental work on GPIO descriptors: have
     gpiod_direction_output() use a logical level, respecting assertion
     polarity through ACTIVE_LOW flags, adding gpiod_direction_output_raw()
     for the case where you want to set that very value.  Add
     gpiochip_get_desc() to fetch a GPIO descriptor from a specific
     offset on a certain chip inside driver code.

   - Switch ACPI GPIO code over to using gpiochip_get_desc() and get rid
     of gpio_to_desc().

   - The ACPI GPIO event handling code has been reworked after
     encountering an actual real life implementation.

   - Support for ACPI GPIO operation regions.

   - Generic GPIO chips can now be assigned labels/names from platform
     data.

   - We now clamp values returned from GPIO drivers to the boolean [0,1]
     range.

   - Some improved documentation on how to use the polarity flag was
     added.

   - a large slew of incremental driver updates and non-critical fixes.
     Some targeted for stable"

* tag 'gpio-v3.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (80 commits)
  gpio: rcar: Add helper variable dev = &pdev->dev
  gpio-lynxpoint: force gpio_get() to return "1" and "0" only
  gpio: unmap gpio irqs properly
  pch_gpio: set value before enabling output direction
  gpio: moxart: Actually set output state in moxart_gpio_direction_output()
  gpio: moxart: Avoid forward declaration
  gpio: mxs: Allow for recursive enable_irq_wake() call
  gpio: samsung: Add missing "break" statement
  gpio: twl4030: Remove redundant assignment
  gpio: dwapb: correct gpio-cells in binding document
  gpio: iop: fix devm_ioremap_resource() return value checking
  pinctrl: coh901: convert driver to use gpiolib irqchip
  pinctrl: nomadik: convert driver to use gpiolib irqchip
  gpio: pl061: convert driver to use gpiolib irqchip
  gpio: add IRQ chip helpers in gpiolib
  pinctrl: nomadik: factor in platform data container
  pinctrl: nomadik: rename secondary to latent
  gpio: Driver for SYSCON-based GPIOs
  gpio: generic: Use platform_device_id->driver_data field for driver flags
  pinctrl: coh901: move irq line locking to resource callbacks
  ...
2014-04-03 16:44:15 -07:00

981 lines
24 KiB
C

/*
* Copyright (c) 2013, Sony Mobile Communications AB.
* Copyright (c) 2013, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* 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/err.h>
#include <linux/irqdomain.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/spinlock.h>
#include "core.h"
#include "pinconf.h"
#include "pinctrl-msm.h"
#include "pinctrl-utils.h"
#define MAX_NR_GPIO 300
/**
* struct msm_pinctrl - state for a pinctrl-msm device
* @dev: device handle.
* @pctrl: pinctrl handle.
* @domain: irqdomain handle.
* @chip: gpiochip handle.
* @irq: parent irq for the TLMM irq_chip.
* @lock: Spinlock to protect register resources as well
* as msm_pinctrl data structures.
* @enabled_irqs: Bitmap of currently enabled irqs.
* @dual_edge_irqs: Bitmap of irqs that need sw emulated dual edge
* detection.
* @soc; Reference to soc_data of platform specific data.
* @regs: Base address for the TLMM register map.
*/
struct msm_pinctrl {
struct device *dev;
struct pinctrl_dev *pctrl;
struct irq_domain *domain;
struct gpio_chip chip;
int irq;
spinlock_t lock;
DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
const struct msm_pinctrl_soc_data *soc;
void __iomem *regs;
};
static int msm_get_groups_count(struct pinctrl_dev *pctldev)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
return pctrl->soc->ngroups;
}
static const char *msm_get_group_name(struct pinctrl_dev *pctldev,
unsigned group)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
return pctrl->soc->groups[group].name;
}
static int msm_get_group_pins(struct pinctrl_dev *pctldev,
unsigned group,
const unsigned **pins,
unsigned *num_pins)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
*pins = pctrl->soc->groups[group].pins;
*num_pins = pctrl->soc->groups[group].npins;
return 0;
}
static const struct pinctrl_ops msm_pinctrl_ops = {
.get_groups_count = msm_get_groups_count,
.get_group_name = msm_get_group_name,
.get_group_pins = msm_get_group_pins,
.dt_node_to_map = pinconf_generic_dt_node_to_map_group,
.dt_free_map = pinctrl_utils_dt_free_map,
};
static int msm_get_functions_count(struct pinctrl_dev *pctldev)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
return pctrl->soc->nfunctions;
}
static const char *msm_get_function_name(struct pinctrl_dev *pctldev,
unsigned function)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
return pctrl->soc->functions[function].name;
}
static int msm_get_function_groups(struct pinctrl_dev *pctldev,
unsigned function,
const char * const **groups,
unsigned * const num_groups)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
*groups = pctrl->soc->functions[function].groups;
*num_groups = pctrl->soc->functions[function].ngroups;
return 0;
}
static int msm_pinmux_enable(struct pinctrl_dev *pctldev,
unsigned function,
unsigned group)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
const struct msm_pingroup *g;
unsigned long flags;
u32 val;
int i;
g = &pctrl->soc->groups[group];
if (WARN_ON(g->mux_bit < 0))
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(g->funcs); i++) {
if (g->funcs[i] == function)
break;
}
if (WARN_ON(i == ARRAY_SIZE(g->funcs)))
return -EINVAL;
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->ctl_reg);
val &= ~(0x7 << g->mux_bit);
val |= i << g->mux_bit;
writel(val, pctrl->regs + g->ctl_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
return 0;
}
static void msm_pinmux_disable(struct pinctrl_dev *pctldev,
unsigned function,
unsigned group)
{
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
const struct msm_pingroup *g;
unsigned long flags;
u32 val;
g = &pctrl->soc->groups[group];
if (WARN_ON(g->mux_bit < 0))
return;
spin_lock_irqsave(&pctrl->lock, flags);
/* Clear the mux bits to select gpio mode */
val = readl(pctrl->regs + g->ctl_reg);
val &= ~(0x7 << g->mux_bit);
writel(val, pctrl->regs + g->ctl_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
static const struct pinmux_ops msm_pinmux_ops = {
.get_functions_count = msm_get_functions_count,
.get_function_name = msm_get_function_name,
.get_function_groups = msm_get_function_groups,
.enable = msm_pinmux_enable,
.disable = msm_pinmux_disable,
};
static int msm_config_reg(struct msm_pinctrl *pctrl,
const struct msm_pingroup *g,
unsigned param,
unsigned *mask,
unsigned *bit)
{
switch (param) {
case PIN_CONFIG_BIAS_DISABLE:
case PIN_CONFIG_BIAS_PULL_DOWN:
case PIN_CONFIG_BIAS_PULL_UP:
*bit = g->pull_bit;
*mask = 3;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
*bit = g->drv_bit;
*mask = 7;
break;
case PIN_CONFIG_OUTPUT:
*bit = g->oe_bit;
*mask = 1;
break;
default:
dev_err(pctrl->dev, "Invalid config param %04x\n", param);
return -ENOTSUPP;
}
return 0;
}
static int msm_config_get(struct pinctrl_dev *pctldev,
unsigned int pin,
unsigned long *config)
{
dev_err(pctldev->dev, "pin_config_set op not supported\n");
return -ENOTSUPP;
}
static int msm_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
unsigned long *configs, unsigned num_configs)
{
dev_err(pctldev->dev, "pin_config_set op not supported\n");
return -ENOTSUPP;
}
#define MSM_NO_PULL 0
#define MSM_PULL_DOWN 1
#define MSM_PULL_UP 3
static unsigned msm_regval_to_drive(u32 val)
{
return (val + 1) * 2;
}
static int msm_config_group_get(struct pinctrl_dev *pctldev,
unsigned int group,
unsigned long *config)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
unsigned param = pinconf_to_config_param(*config);
unsigned mask;
unsigned arg;
unsigned bit;
int ret;
u32 val;
g = &pctrl->soc->groups[group];
ret = msm_config_reg(pctrl, g, param, &mask, &bit);
if (ret < 0)
return ret;
val = readl(pctrl->regs + g->ctl_reg);
arg = (val >> bit) & mask;
/* Convert register value to pinconf value */
switch (param) {
case PIN_CONFIG_BIAS_DISABLE:
arg = arg == MSM_NO_PULL;
break;
case PIN_CONFIG_BIAS_PULL_DOWN:
arg = arg == MSM_PULL_DOWN;
break;
case PIN_CONFIG_BIAS_PULL_UP:
arg = arg == MSM_PULL_UP;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
arg = msm_regval_to_drive(arg);
break;
case PIN_CONFIG_OUTPUT:
/* Pin is not output */
if (!arg)
return -EINVAL;
val = readl(pctrl->regs + g->io_reg);
arg = !!(val & BIT(g->in_bit));
break;
default:
dev_err(pctrl->dev, "Unsupported config parameter: %x\n",
param);
return -EINVAL;
}
*config = pinconf_to_config_packed(param, arg);
return 0;
}
static int msm_config_group_set(struct pinctrl_dev *pctldev,
unsigned group,
unsigned long *configs,
unsigned num_configs)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
unsigned long flags;
unsigned param;
unsigned mask;
unsigned arg;
unsigned bit;
int ret;
u32 val;
int i;
g = &pctrl->soc->groups[group];
for (i = 0; i < num_configs; i++) {
param = pinconf_to_config_param(configs[i]);
arg = pinconf_to_config_argument(configs[i]);
ret = msm_config_reg(pctrl, g, param, &mask, &bit);
if (ret < 0)
return ret;
/* Convert pinconf values to register values */
switch (param) {
case PIN_CONFIG_BIAS_DISABLE:
arg = MSM_NO_PULL;
break;
case PIN_CONFIG_BIAS_PULL_DOWN:
arg = MSM_PULL_DOWN;
break;
case PIN_CONFIG_BIAS_PULL_UP:
arg = MSM_PULL_UP;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
/* Check for invalid values */
if (arg > 16 || arg < 2 || (arg % 2) != 0)
arg = -1;
else
arg = (arg / 2) - 1;
break;
case PIN_CONFIG_OUTPUT:
/* set output value */
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->io_reg);
if (arg)
val |= BIT(g->out_bit);
else
val &= ~BIT(g->out_bit);
writel(val, pctrl->regs + g->io_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
/* enable output */
arg = 1;
break;
default:
dev_err(pctrl->dev, "Unsupported config parameter: %x\n",
param);
return -EINVAL;
}
/* Range-check user-supplied value */
if (arg & ~mask) {
dev_err(pctrl->dev, "config %x: %x is invalid\n", param, arg);
return -EINVAL;
}
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->ctl_reg);
val &= ~(mask << bit);
val |= arg << bit;
writel(val, pctrl->regs + g->ctl_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
return 0;
}
static const struct pinconf_ops msm_pinconf_ops = {
.pin_config_get = msm_config_get,
.pin_config_set = msm_config_set,
.pin_config_group_get = msm_config_group_get,
.pin_config_group_set = msm_config_group_set,
};
static struct pinctrl_desc msm_pinctrl_desc = {
.pctlops = &msm_pinctrl_ops,
.pmxops = &msm_pinmux_ops,
.confops = &msm_pinconf_ops,
.owner = THIS_MODULE,
};
static int msm_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
unsigned long flags;
u32 val;
g = &pctrl->soc->groups[offset];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->ctl_reg);
val &= ~BIT(g->oe_bit);
writel(val, pctrl->regs + g->ctl_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
return 0;
}
static int msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
unsigned long flags;
u32 val;
g = &pctrl->soc->groups[offset];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->io_reg);
if (value)
val |= BIT(g->out_bit);
else
val &= ~BIT(g->out_bit);
writel(val, pctrl->regs + g->io_reg);
val = readl(pctrl->regs + g->ctl_reg);
val |= BIT(g->oe_bit);
writel(val, pctrl->regs + g->ctl_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
return 0;
}
static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
u32 val;
g = &pctrl->soc->groups[offset];
val = readl(pctrl->regs + g->io_reg);
return !!(val & BIT(g->in_bit));
}
static void msm_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
unsigned long flags;
u32 val;
g = &pctrl->soc->groups[offset];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->io_reg);
if (value)
val |= BIT(g->out_bit);
else
val &= ~BIT(g->out_bit);
writel(val, pctrl->regs + g->io_reg);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
static int msm_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
return irq_find_mapping(pctrl->domain, offset);
}
static int msm_gpio_request(struct gpio_chip *chip, unsigned offset)
{
int gpio = chip->base + offset;
return pinctrl_request_gpio(gpio);
}
static void msm_gpio_free(struct gpio_chip *chip, unsigned offset)
{
int gpio = chip->base + offset;
return pinctrl_free_gpio(gpio);
}
#ifdef CONFIG_DEBUG_FS
#include <linux/seq_file.h>
static void msm_gpio_dbg_show_one(struct seq_file *s,
struct pinctrl_dev *pctldev,
struct gpio_chip *chip,
unsigned offset,
unsigned gpio)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = container_of(chip, struct msm_pinctrl, chip);
unsigned func;
int is_out;
int drive;
int pull;
u32 ctl_reg;
static const char * const pulls[] = {
"no pull",
"pull down",
"keeper",
"pull up"
};
g = &pctrl->soc->groups[offset];
ctl_reg = readl(pctrl->regs + g->ctl_reg);
is_out = !!(ctl_reg & BIT(g->oe_bit));
func = (ctl_reg >> g->mux_bit) & 7;
drive = (ctl_reg >> g->drv_bit) & 7;
pull = (ctl_reg >> g->pull_bit) & 3;
seq_printf(s, " %-8s: %-3s %d", g->name, is_out ? "out" : "in", func);
seq_printf(s, " %dmA", msm_regval_to_drive(drive));
seq_printf(s, " %s", pulls[pull]);
}
static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
unsigned gpio = chip->base;
unsigned i;
for (i = 0; i < chip->ngpio; i++, gpio++) {
msm_gpio_dbg_show_one(s, NULL, chip, i, gpio);
seq_puts(s, "\n");
}
}
#else
#define msm_gpio_dbg_show NULL
#endif
static struct gpio_chip msm_gpio_template = {
.direction_input = msm_gpio_direction_input,
.direction_output = msm_gpio_direction_output,
.get = msm_gpio_get,
.set = msm_gpio_set,
.to_irq = msm_gpio_to_irq,
.request = msm_gpio_request,
.free = msm_gpio_free,
.dbg_show = msm_gpio_dbg_show,
};
/* For dual-edge interrupts in software, since some hardware has no
* such support:
*
* At appropriate moments, this function may be called to flip the polarity
* settings of both-edge irq lines to try and catch the next edge.
*
* The attempt is considered successful if:
* - the status bit goes high, indicating that an edge was caught, or
* - the input value of the gpio doesn't change during the attempt.
* If the value changes twice during the process, that would cause the first
* test to fail but would force the second, as two opposite
* transitions would cause a detection no matter the polarity setting.
*
* The do-loop tries to sledge-hammer closed the timing hole between
* the initial value-read and the polarity-write - if the line value changes
* during that window, an interrupt is lost, the new polarity setting is
* incorrect, and the first success test will fail, causing a retry.
*
* Algorithm comes from Google's msmgpio driver.
*/
static void msm_gpio_update_dual_edge_pos(struct msm_pinctrl *pctrl,
const struct msm_pingroup *g,
struct irq_data *d)
{
int loop_limit = 100;
unsigned val, val2, intstat;
unsigned pol;
do {
val = readl(pctrl->regs + g->io_reg) & BIT(g->in_bit);
pol = readl(pctrl->regs + g->intr_cfg_reg);
pol ^= BIT(g->intr_polarity_bit);
writel(pol, pctrl->regs + g->intr_cfg_reg);
val2 = readl(pctrl->regs + g->io_reg) & BIT(g->in_bit);
intstat = readl(pctrl->regs + g->intr_status_reg);
if (intstat || (val == val2))
return;
} while (loop_limit-- > 0);
dev_err(pctrl->dev, "dual-edge irq failed to stabilize, %#08x != %#08x\n",
val, val2);
}
static void msm_gpio_irq_mask(struct irq_data *d)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl;
unsigned long flags;
u32 val;
pctrl = irq_data_get_irq_chip_data(d);
g = &pctrl->soc->groups[d->hwirq];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->intr_cfg_reg);
val &= ~BIT(g->intr_enable_bit);
writel(val, pctrl->regs + g->intr_cfg_reg);
clear_bit(d->hwirq, pctrl->enabled_irqs);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
static void msm_gpio_irq_unmask(struct irq_data *d)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl;
unsigned long flags;
u32 val;
pctrl = irq_data_get_irq_chip_data(d);
g = &pctrl->soc->groups[d->hwirq];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->intr_status_reg);
val &= ~BIT(g->intr_status_bit);
writel(val, pctrl->regs + g->intr_status_reg);
val = readl(pctrl->regs + g->intr_cfg_reg);
val |= BIT(g->intr_enable_bit);
writel(val, pctrl->regs + g->intr_cfg_reg);
set_bit(d->hwirq, pctrl->enabled_irqs);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
static void msm_gpio_irq_ack(struct irq_data *d)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl;
unsigned long flags;
u32 val;
pctrl = irq_data_get_irq_chip_data(d);
g = &pctrl->soc->groups[d->hwirq];
spin_lock_irqsave(&pctrl->lock, flags);
val = readl(pctrl->regs + g->intr_status_reg);
val &= ~BIT(g->intr_status_bit);
writel(val, pctrl->regs + g->intr_status_reg);
if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
msm_gpio_update_dual_edge_pos(pctrl, g, d);
spin_unlock_irqrestore(&pctrl->lock, flags);
}
#define INTR_TARGET_PROC_APPS 4
static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl;
unsigned long flags;
u32 val;
pctrl = irq_data_get_irq_chip_data(d);
g = &pctrl->soc->groups[d->hwirq];
spin_lock_irqsave(&pctrl->lock, flags);
/*
* For hw without possibility of detecting both edges
*/
if (g->intr_detection_width == 1 && type == IRQ_TYPE_EDGE_BOTH)
set_bit(d->hwirq, pctrl->dual_edge_irqs);
else
clear_bit(d->hwirq, pctrl->dual_edge_irqs);
/* Route interrupts to application cpu */
val = readl(pctrl->regs + g->intr_target_reg);
val &= ~(7 << g->intr_target_bit);
val |= INTR_TARGET_PROC_APPS << g->intr_target_bit;
writel(val, pctrl->regs + g->intr_target_reg);
/* Update configuration for gpio.
* RAW_STATUS_EN is left on for all gpio irqs. Due to the
* internal circuitry of TLMM, toggling the RAW_STATUS
* could cause the INTR_STATUS to be set for EDGE interrupts.
*/
val = readl(pctrl->regs + g->intr_cfg_reg);
val |= BIT(g->intr_raw_status_bit);
if (g->intr_detection_width == 2) {
val &= ~(3 << g->intr_detection_bit);
val &= ~(1 << g->intr_polarity_bit);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
val |= 1 << g->intr_detection_bit;
val |= BIT(g->intr_polarity_bit);
break;
case IRQ_TYPE_EDGE_FALLING:
val |= 2 << g->intr_detection_bit;
val |= BIT(g->intr_polarity_bit);
break;
case IRQ_TYPE_EDGE_BOTH:
val |= 3 << g->intr_detection_bit;
val |= BIT(g->intr_polarity_bit);
break;
case IRQ_TYPE_LEVEL_LOW:
break;
case IRQ_TYPE_LEVEL_HIGH:
val |= BIT(g->intr_polarity_bit);
break;
}
} else if (g->intr_detection_width == 1) {
val &= ~(1 << g->intr_detection_bit);
val &= ~(1 << g->intr_polarity_bit);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
val |= BIT(g->intr_detection_bit);
val |= BIT(g->intr_polarity_bit);
break;
case IRQ_TYPE_EDGE_FALLING:
val |= BIT(g->intr_detection_bit);
break;
case IRQ_TYPE_EDGE_BOTH:
val |= BIT(g->intr_detection_bit);
break;
case IRQ_TYPE_LEVEL_LOW:
break;
case IRQ_TYPE_LEVEL_HIGH:
val |= BIT(g->intr_polarity_bit);
break;
}
} else {
BUG();
}
writel(val, pctrl->regs + g->intr_cfg_reg);
if (test_bit(d->hwirq, pctrl->dual_edge_irqs))
msm_gpio_update_dual_edge_pos(pctrl, g, d);
spin_unlock_irqrestore(&pctrl->lock, flags);
if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
__irq_set_handler_locked(d->irq, handle_level_irq);
else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
__irq_set_handler_locked(d->irq, handle_edge_irq);
return 0;
}
static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct msm_pinctrl *pctrl;
unsigned long flags;
pctrl = irq_data_get_irq_chip_data(d);
spin_lock_irqsave(&pctrl->lock, flags);
irq_set_irq_wake(pctrl->irq, on);
spin_unlock_irqrestore(&pctrl->lock, flags);
return 0;
}
static int msm_gpio_irq_reqres(struct irq_data *d)
{
struct msm_pinctrl *pctrl = irq_data_get_irq_chip_data(d);
if (gpio_lock_as_irq(&pctrl->chip, d->hwirq)) {
dev_err(pctrl->dev, "unable to lock HW IRQ %lu for IRQ\n",
d->hwirq);
return -EINVAL;
}
return 0;
}
static void msm_gpio_irq_relres(struct irq_data *d)
{
struct msm_pinctrl *pctrl = irq_data_get_irq_chip_data(d);
gpio_unlock_as_irq(&pctrl->chip, d->hwirq);
}
static struct irq_chip msm_gpio_irq_chip = {
.name = "msmgpio",
.irq_mask = msm_gpio_irq_mask,
.irq_unmask = msm_gpio_irq_unmask,
.irq_ack = msm_gpio_irq_ack,
.irq_set_type = msm_gpio_irq_set_type,
.irq_set_wake = msm_gpio_irq_set_wake,
.irq_request_resources = msm_gpio_irq_reqres,
.irq_release_resources = msm_gpio_irq_relres,
};
static void msm_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
{
const struct msm_pingroup *g;
struct msm_pinctrl *pctrl = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_get_chip(irq);
int irq_pin;
int handled = 0;
u32 val;
int i;
chained_irq_enter(chip, desc);
/*
* Each pin has it's own IRQ status register, so use
* enabled_irq bitmap to limit the number of reads.
*/
for_each_set_bit(i, pctrl->enabled_irqs, pctrl->chip.ngpio) {
g = &pctrl->soc->groups[i];
val = readl(pctrl->regs + g->intr_status_reg);
if (val & BIT(g->intr_status_bit)) {
irq_pin = irq_find_mapping(pctrl->domain, i);
generic_handle_irq(irq_pin);
handled++;
}
}
/* No interrupts were flagged */
if (handled == 0)
handle_bad_irq(irq, desc);
chained_irq_exit(chip, desc);
}
/*
* This lock class tells lockdep that GPIO irqs are in a different
* category than their parents, so it won't report false recursion.
*/
static struct lock_class_key gpio_lock_class;
static int msm_gpio_init(struct msm_pinctrl *pctrl)
{
struct gpio_chip *chip;
int irq;
int ret;
int i;
int r;
unsigned ngpio = pctrl->soc->ngpios;
if (WARN_ON(ngpio > MAX_NR_GPIO))
return -EINVAL;
chip = &pctrl->chip;
chip->base = 0;
chip->ngpio = ngpio;
chip->label = dev_name(pctrl->dev);
chip->dev = pctrl->dev;
chip->owner = THIS_MODULE;
chip->of_node = pctrl->dev->of_node;
ret = gpiochip_add(&pctrl->chip);
if (ret) {
dev_err(pctrl->dev, "Failed register gpiochip\n");
return ret;
}
ret = gpiochip_add_pin_range(&pctrl->chip, dev_name(pctrl->dev), 0, 0, chip->ngpio);
if (ret) {
dev_err(pctrl->dev, "Failed to add pin range\n");
return ret;
}
pctrl->domain = irq_domain_add_linear(pctrl->dev->of_node, chip->ngpio,
&irq_domain_simple_ops, NULL);
if (!pctrl->domain) {
dev_err(pctrl->dev, "Failed to register irq domain\n");
r = gpiochip_remove(&pctrl->chip);
return -ENOSYS;
}
for (i = 0; i < chip->ngpio; i++) {
irq = irq_create_mapping(pctrl->domain, i);
irq_set_lockdep_class(irq, &gpio_lock_class);
irq_set_chip_and_handler(irq, &msm_gpio_irq_chip, handle_edge_irq);
irq_set_chip_data(irq, pctrl);
}
irq_set_handler_data(pctrl->irq, pctrl);
irq_set_chained_handler(pctrl->irq, msm_gpio_irq_handler);
return 0;
}
int msm_pinctrl_probe(struct platform_device *pdev,
const struct msm_pinctrl_soc_data *soc_data)
{
struct msm_pinctrl *pctrl;
struct resource *res;
int ret;
pctrl = devm_kzalloc(&pdev->dev, sizeof(*pctrl), GFP_KERNEL);
if (!pctrl) {
dev_err(&pdev->dev, "Can't allocate msm_pinctrl\n");
return -ENOMEM;
}
pctrl->dev = &pdev->dev;
pctrl->soc = soc_data;
pctrl->chip = msm_gpio_template;
spin_lock_init(&pctrl->lock);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
pctrl->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(pctrl->regs))
return PTR_ERR(pctrl->regs);
pctrl->irq = platform_get_irq(pdev, 0);
if (pctrl->irq < 0) {
dev_err(&pdev->dev, "No interrupt defined for msmgpio\n");
return pctrl->irq;
}
msm_pinctrl_desc.name = dev_name(&pdev->dev);
msm_pinctrl_desc.pins = pctrl->soc->pins;
msm_pinctrl_desc.npins = pctrl->soc->npins;
pctrl->pctrl = pinctrl_register(&msm_pinctrl_desc, &pdev->dev, pctrl);
if (!pctrl->pctrl) {
dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
return -ENODEV;
}
ret = msm_gpio_init(pctrl);
if (ret) {
pinctrl_unregister(pctrl->pctrl);
return ret;
}
platform_set_drvdata(pdev, pctrl);
dev_dbg(&pdev->dev, "Probed Qualcomm pinctrl driver\n");
return 0;
}
EXPORT_SYMBOL(msm_pinctrl_probe);
int msm_pinctrl_remove(struct platform_device *pdev)
{
struct msm_pinctrl *pctrl = platform_get_drvdata(pdev);
int ret;
ret = gpiochip_remove(&pctrl->chip);
if (ret) {
dev_err(&pdev->dev, "Failed to remove gpiochip\n");
return ret;
}
irq_set_chained_handler(pctrl->irq, NULL);
irq_domain_remove(pctrl->domain);
pinctrl_unregister(pctrl->pctrl);
return 0;
}
EXPORT_SYMBOL(msm_pinctrl_remove);