linux/drivers/gpio/gpio-pch.c
Daniel Krueger 2ddf6cd67c pch_gpio: set value before enabling output direction
This ensures that the output signal does not toggle if set to high.

Signed-off-by: Daniel Krueger <daniel.krueger@systec-electronic.com>
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-27 10:20:29 +01:00

545 lines
14 KiB
C

/*
* Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
*
* 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; version 2 of the License.
*
* 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.
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#define PCH_EDGE_FALLING 0
#define PCH_EDGE_RISING BIT(0)
#define PCH_LEVEL_L BIT(1)
#define PCH_LEVEL_H (BIT(0) | BIT(1))
#define PCH_EDGE_BOTH BIT(2)
#define PCH_IM_MASK (BIT(0) | BIT(1) | BIT(2))
#define PCH_IRQ_BASE 24
struct pch_regs {
u32 ien;
u32 istatus;
u32 idisp;
u32 iclr;
u32 imask;
u32 imaskclr;
u32 po;
u32 pi;
u32 pm;
u32 im0;
u32 im1;
u32 reserved[3];
u32 gpio_use_sel;
u32 reset;
};
enum pch_type_t {
INTEL_EG20T_PCH,
OKISEMI_ML7223m_IOH, /* LAPIS Semiconductor ML7223 IOH PCIe Bus-m */
OKISEMI_ML7223n_IOH /* LAPIS Semiconductor ML7223 IOH PCIe Bus-n */
};
/* Specifies number of GPIO PINS */
static int gpio_pins[] = {
[INTEL_EG20T_PCH] = 12,
[OKISEMI_ML7223m_IOH] = 8,
[OKISEMI_ML7223n_IOH] = 8,
};
/**
* struct pch_gpio_reg_data - The register store data.
* @ien_reg: To store contents of IEN register.
* @imask_reg: To store contents of IMASK register.
* @po_reg: To store contents of PO register.
* @pm_reg: To store contents of PM register.
* @im0_reg: To store contents of IM0 register.
* @im1_reg: To store contents of IM1 register.
* @gpio_use_sel_reg : To store contents of GPIO_USE_SEL register.
* (Only ML7223 Bus-n)
*/
struct pch_gpio_reg_data {
u32 ien_reg;
u32 imask_reg;
u32 po_reg;
u32 pm_reg;
u32 im0_reg;
u32 im1_reg;
u32 gpio_use_sel_reg;
};
/**
* struct pch_gpio - GPIO private data structure.
* @base: PCI base address of Memory mapped I/O register.
* @reg: Memory mapped PCH GPIO register list.
* @dev: Pointer to device structure.
* @gpio: Data for GPIO infrastructure.
* @pch_gpio_reg: Memory mapped Register data is saved here
* when suspend.
* @lock: Used for register access protection
* @irq_base: Save base of IRQ number for interrupt
* @ioh: IOH ID
* @spinlock: Used for register access protection
*/
struct pch_gpio {
void __iomem *base;
struct pch_regs __iomem *reg;
struct device *dev;
struct gpio_chip gpio;
struct pch_gpio_reg_data pch_gpio_reg;
int irq_base;
enum pch_type_t ioh;
spinlock_t spinlock;
};
static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
{
u32 reg_val;
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
unsigned long flags;
spin_lock_irqsave(&chip->spinlock, flags);
reg_val = ioread32(&chip->reg->po);
if (val)
reg_val |= (1 << nr);
else
reg_val &= ~(1 << nr);
iowrite32(reg_val, &chip->reg->po);
spin_unlock_irqrestore(&chip->spinlock, flags);
}
static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
{
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
return ioread32(&chip->reg->pi) & (1 << nr);
}
static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
int val)
{
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
u32 pm;
u32 reg_val;
unsigned long flags;
spin_lock_irqsave(&chip->spinlock, flags);
reg_val = ioread32(&chip->reg->po);
if (val)
reg_val |= (1 << nr);
else
reg_val &= ~(1 << nr);
iowrite32(reg_val, &chip->reg->po);
pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
pm |= (1 << nr);
iowrite32(pm, &chip->reg->pm);
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
{
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
u32 pm;
unsigned long flags;
spin_lock_irqsave(&chip->spinlock, flags);
pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
pm &= ~(1 << nr);
iowrite32(pm, &chip->reg->pm);
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
/*
* Save register configuration and disable interrupts.
*/
static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
{
chip->pch_gpio_reg.ien_reg = ioread32(&chip->reg->ien);
chip->pch_gpio_reg.imask_reg = ioread32(&chip->reg->imask);
chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
chip->pch_gpio_reg.im0_reg = ioread32(&chip->reg->im0);
if (chip->ioh == INTEL_EG20T_PCH)
chip->pch_gpio_reg.im1_reg = ioread32(&chip->reg->im1);
if (chip->ioh == OKISEMI_ML7223n_IOH)
chip->pch_gpio_reg.gpio_use_sel_reg =\
ioread32(&chip->reg->gpio_use_sel);
}
/*
* This function restores the register configuration of the GPIO device.
*/
static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
{
iowrite32(chip->pch_gpio_reg.ien_reg, &chip->reg->ien);
iowrite32(chip->pch_gpio_reg.imask_reg, &chip->reg->imask);
/* to store contents of PO register */
iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
/* to store contents of PM register */
iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
iowrite32(chip->pch_gpio_reg.im0_reg, &chip->reg->im0);
if (chip->ioh == INTEL_EG20T_PCH)
iowrite32(chip->pch_gpio_reg.im1_reg, &chip->reg->im1);
if (chip->ioh == OKISEMI_ML7223n_IOH)
iowrite32(chip->pch_gpio_reg.gpio_use_sel_reg,
&chip->reg->gpio_use_sel);
}
static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
{
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
return chip->irq_base + offset;
}
static void pch_gpio_setup(struct pch_gpio *chip)
{
struct gpio_chip *gpio = &chip->gpio;
gpio->label = dev_name(chip->dev);
gpio->dev = chip->dev;
gpio->owner = THIS_MODULE;
gpio->direction_input = pch_gpio_direction_input;
gpio->get = pch_gpio_get;
gpio->direction_output = pch_gpio_direction_output;
gpio->set = pch_gpio_set;
gpio->dbg_show = NULL;
gpio->base = -1;
gpio->ngpio = gpio_pins[chip->ioh];
gpio->can_sleep = false;
gpio->to_irq = pch_gpio_to_irq;
}
static int pch_irq_type(struct irq_data *d, unsigned int type)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct pch_gpio *chip = gc->private;
u32 im, im_pos, val;
u32 __iomem *im_reg;
unsigned long flags;
int ch, irq = d->irq;
ch = irq - chip->irq_base;
if (irq <= chip->irq_base + 7) {
im_reg = &chip->reg->im0;
im_pos = ch;
} else {
im_reg = &chip->reg->im1;
im_pos = ch - 8;
}
dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d\n",
__func__, irq, type, ch, im_pos);
spin_lock_irqsave(&chip->spinlock, flags);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
val = PCH_EDGE_RISING;
break;
case IRQ_TYPE_EDGE_FALLING:
val = PCH_EDGE_FALLING;
break;
case IRQ_TYPE_EDGE_BOTH:
val = PCH_EDGE_BOTH;
break;
case IRQ_TYPE_LEVEL_HIGH:
val = PCH_LEVEL_H;
break;
case IRQ_TYPE_LEVEL_LOW:
val = PCH_LEVEL_L;
break;
default:
goto unlock;
}
/* Set interrupt mode */
im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
iowrite32(im | (val << (im_pos * 4)), im_reg);
/* And the handler */
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);
unlock:
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
static void pch_irq_unmask(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct pch_gpio *chip = gc->private;
iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imaskclr);
}
static void pch_irq_mask(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct pch_gpio *chip = gc->private;
iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->imask);
}
static void pch_irq_ack(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct pch_gpio *chip = gc->private;
iowrite32(1 << (d->irq - chip->irq_base), &chip->reg->iclr);
}
static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
{
struct pch_gpio *chip = dev_id;
u32 reg_val = ioread32(&chip->reg->istatus);
int i, ret = IRQ_NONE;
for (i = 0; i < gpio_pins[chip->ioh]; i++) {
if (reg_val & BIT(i)) {
dev_dbg(chip->dev, "%s:[%d]:irq=%d status=0x%x\n",
__func__, i, irq, reg_val);
generic_handle_irq(chip->irq_base + i);
ret = IRQ_HANDLED;
}
}
return ret;
}
static void pch_gpio_alloc_generic_chip(struct pch_gpio *chip,
unsigned int irq_start, unsigned int num)
{
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
gc = irq_alloc_generic_chip("pch_gpio", 1, irq_start, chip->base,
handle_simple_irq);
gc->private = chip;
ct = gc->chip_types;
ct->chip.irq_ack = pch_irq_ack;
ct->chip.irq_mask = pch_irq_mask;
ct->chip.irq_unmask = pch_irq_unmask;
ct->chip.irq_set_type = pch_irq_type;
irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
IRQ_NOREQUEST | IRQ_NOPROBE, 0);
}
static int pch_gpio_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
s32 ret;
struct pch_gpio *chip;
int irq_base;
u32 msk;
chip = kzalloc(sizeof(*chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
chip->dev = &pdev->dev;
ret = pci_enable_device(pdev);
if (ret) {
dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
goto err_pci_enable;
}
ret = pci_request_regions(pdev, KBUILD_MODNAME);
if (ret) {
dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
goto err_request_regions;
}
chip->base = pci_iomap(pdev, 1, 0);
if (!chip->base) {
dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
ret = -ENOMEM;
goto err_iomap;
}
if (pdev->device == 0x8803)
chip->ioh = INTEL_EG20T_PCH;
else if (pdev->device == 0x8014)
chip->ioh = OKISEMI_ML7223m_IOH;
else if (pdev->device == 0x8043)
chip->ioh = OKISEMI_ML7223n_IOH;
chip->reg = chip->base;
pci_set_drvdata(pdev, chip);
spin_lock_init(&chip->spinlock);
pch_gpio_setup(chip);
ret = gpiochip_add(&chip->gpio);
if (ret) {
dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
goto err_gpiochip_add;
}
irq_base = irq_alloc_descs(-1, 0, gpio_pins[chip->ioh], NUMA_NO_NODE);
if (irq_base < 0) {
dev_warn(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
chip->irq_base = -1;
goto end;
}
chip->irq_base = irq_base;
/* Mask all interrupts, but enable them */
msk = (1 << gpio_pins[chip->ioh]) - 1;
iowrite32(msk, &chip->reg->imask);
iowrite32(msk, &chip->reg->ien);
ret = request_irq(pdev->irq, pch_gpio_handler,
IRQF_SHARED, KBUILD_MODNAME, chip);
if (ret != 0) {
dev_err(&pdev->dev,
"%s request_irq failed\n", __func__);
goto err_request_irq;
}
pch_gpio_alloc_generic_chip(chip, irq_base, gpio_pins[chip->ioh]);
end:
return 0;
err_request_irq:
irq_free_descs(irq_base, gpio_pins[chip->ioh]);
if (gpiochip_remove(&chip->gpio))
dev_err(&pdev->dev, "%s gpiochip_remove failed\n", __func__);
err_gpiochip_add:
pci_iounmap(pdev, chip->base);
err_iomap:
pci_release_regions(pdev);
err_request_regions:
pci_disable_device(pdev);
err_pci_enable:
kfree(chip);
dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
return ret;
}
static void pch_gpio_remove(struct pci_dev *pdev)
{
int err;
struct pch_gpio *chip = pci_get_drvdata(pdev);
if (chip->irq_base != -1) {
free_irq(pdev->irq, chip);
irq_free_descs(chip->irq_base, gpio_pins[chip->ioh]);
}
err = gpiochip_remove(&chip->gpio);
if (err)
dev_err(&pdev->dev, "Failed gpiochip_remove\n");
pci_iounmap(pdev, chip->base);
pci_release_regions(pdev);
pci_disable_device(pdev);
kfree(chip);
}
#ifdef CONFIG_PM
static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
{
s32 ret;
struct pch_gpio *chip = pci_get_drvdata(pdev);
unsigned long flags;
spin_lock_irqsave(&chip->spinlock, flags);
pch_gpio_save_reg_conf(chip);
spin_unlock_irqrestore(&chip->spinlock, flags);
ret = pci_save_state(pdev);
if (ret) {
dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
return ret;
}
pci_disable_device(pdev);
pci_set_power_state(pdev, PCI_D0);
ret = pci_enable_wake(pdev, PCI_D0, 1);
if (ret)
dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
return 0;
}
static int pch_gpio_resume(struct pci_dev *pdev)
{
s32 ret;
struct pch_gpio *chip = pci_get_drvdata(pdev);
unsigned long flags;
ret = pci_enable_wake(pdev, PCI_D0, 0);
pci_set_power_state(pdev, PCI_D0);
ret = pci_enable_device(pdev);
if (ret) {
dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
return ret;
}
pci_restore_state(pdev);
spin_lock_irqsave(&chip->spinlock, flags);
iowrite32(0x01, &chip->reg->reset);
iowrite32(0x00, &chip->reg->reset);
pch_gpio_restore_reg_conf(chip);
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
#else
#define pch_gpio_suspend NULL
#define pch_gpio_resume NULL
#endif
#define PCI_VENDOR_ID_ROHM 0x10DB
static const struct pci_device_id pch_gpio_pcidev_id[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8043) },
{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8803) },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
static struct pci_driver pch_gpio_driver = {
.name = "pch_gpio",
.id_table = pch_gpio_pcidev_id,
.probe = pch_gpio_probe,
.remove = pch_gpio_remove,
.suspend = pch_gpio_suspend,
.resume = pch_gpio_resume
};
module_pci_driver(pch_gpio_driver);
MODULE_DESCRIPTION("PCH GPIO PCI Driver");
MODULE_LICENSE("GPL");