linux/drivers/mfd/twl6030-irq.c
Santosh Shilimkar 49dcd070d0 mfd: Set twl6030 irq_wake infrastructure up
TWL6030 devices have an interrupt line which is connected to
application processor like OMAP. These devices support multiple features
such as MMC card detect, USB cable detect, RTC interrupt, etc. that must
wake up the application processor.

With this change, TWL6030 client drivers can make use of
irq_wake() if the wakeup is desirable on it's irq events.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-10-24 14:09:13 +02:00

378 lines
10 KiB
C

/*
* twl6030-irq.c - TWL6030 irq support
*
* Copyright (C) 2005-2009 Texas Instruments, Inc.
*
* Modifications to defer interrupt handling to a kernel thread:
* Copyright (C) 2006 MontaVista Software, Inc.
*
* Based on tlv320aic23.c:
* Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
*
* Code cleanup and modifications to IRQ handler.
* by syed khasim <x0khasim@ti.com>
*
* TWL6030 specific code and IRQ handling changes by
* Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com>
* Balaji T K <balajitk@ti.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.
*
* 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/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kthread.h>
#include <linux/i2c/twl.h>
#include <linux/platform_device.h>
#include "twl-core.h"
/*
* TWL6030 (unlike its predecessors, which had two level interrupt handling)
* three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.
* It exposes status bits saying who has raised an interrupt. There are
* three mask registers that corresponds to these status registers, that
* enables/disables these interrupts.
*
* We set up IRQs starting at a platform-specified base. An interrupt map table,
* specifies mapping between interrupt number and the associated module.
*
*/
static int twl6030_interrupt_mapping[24] = {
PWR_INTR_OFFSET, /* Bit 0 PWRON */
PWR_INTR_OFFSET, /* Bit 1 RPWRON */
PWR_INTR_OFFSET, /* Bit 2 BAT_VLOW */
RTC_INTR_OFFSET, /* Bit 3 RTC_ALARM */
RTC_INTR_OFFSET, /* Bit 4 RTC_PERIOD */
HOTDIE_INTR_OFFSET, /* Bit 5 HOT_DIE */
SMPSLDO_INTR_OFFSET, /* Bit 6 VXXX_SHORT */
SMPSLDO_INTR_OFFSET, /* Bit 7 VMMC_SHORT */
SMPSLDO_INTR_OFFSET, /* Bit 8 VUSIM_SHORT */
BATDETECT_INTR_OFFSET, /* Bit 9 BAT */
SIMDETECT_INTR_OFFSET, /* Bit 10 SIM */
MMCDETECT_INTR_OFFSET, /* Bit 11 MMC */
RSV_INTR_OFFSET, /* Bit 12 Reserved */
MADC_INTR_OFFSET, /* Bit 13 GPADC_RT_EOC */
MADC_INTR_OFFSET, /* Bit 14 GPADC_SW_EOC */
GASGAUGE_INTR_OFFSET, /* Bit 15 CC_AUTOCAL */
USBOTG_INTR_OFFSET, /* Bit 16 ID_WKUP */
USBOTG_INTR_OFFSET, /* Bit 17 VBUS_WKUP */
USBOTG_INTR_OFFSET, /* Bit 18 ID */
USB_PRES_INTR_OFFSET, /* Bit 19 VBUS */
CHARGER_INTR_OFFSET, /* Bit 20 CHRG_CTRL */
CHARGERFAULT_INTR_OFFSET, /* Bit 21 EXT_CHRG */
CHARGERFAULT_INTR_OFFSET, /* Bit 22 INT_CHRG */
RSV_INTR_OFFSET, /* Bit 23 Reserved */
};
/*----------------------------------------------------------------------*/
static unsigned twl6030_irq_base;
static struct completion irq_event;
/*
* This thread processes interrupts reported by the Primary Interrupt Handler.
*/
static int twl6030_irq_thread(void *data)
{
long irq = (long)data;
static unsigned i2c_errors;
static const unsigned max_i2c_errors = 100;
int ret;
current->flags |= PF_NOFREEZE;
while (!kthread_should_stop()) {
int i;
union {
u8 bytes[4];
u32 int_sts;
} sts;
/* Wait for IRQ, then read PIH irq status (also blocking) */
wait_for_completion_interruptible(&irq_event);
/* read INT_STS_A, B and C in one shot using a burst read */
ret = twl_i2c_read(TWL_MODULE_PIH, sts.bytes,
REG_INT_STS_A, 3);
if (ret) {
pr_warning("twl6030: I2C error %d reading PIH ISR\n",
ret);
if (++i2c_errors >= max_i2c_errors) {
printk(KERN_ERR "Maximum I2C error count"
" exceeded. Terminating %s.\n",
__func__);
break;
}
complete(&irq_event);
continue;
}
sts.bytes[3] = 0; /* Only 24 bits are valid*/
/*
* Since VBUS status bit is not reliable for VBUS disconnect
* use CHARGER VBUS detection status bit instead.
*/
if (sts.bytes[2] & 0x10)
sts.bytes[2] |= 0x08;
for (i = 0; sts.int_sts; sts.int_sts >>= 1, i++) {
local_irq_disable();
if (sts.int_sts & 0x1) {
int module_irq = twl6030_irq_base +
twl6030_interrupt_mapping[i];
generic_handle_irq(module_irq);
}
local_irq_enable();
}
ret = twl_i2c_write(TWL_MODULE_PIH, sts.bytes,
REG_INT_STS_A, 3); /* clear INT_STS_A */
if (ret)
pr_warning("twl6030: I2C error in clearing PIH ISR\n");
enable_irq(irq);
}
return 0;
}
/*
* handle_twl6030_int() is the desc->handle method for the twl6030 interrupt.
* This is a chained interrupt, so there is no desc->action method for it.
* Now we need to query the interrupt controller in the twl6030 to determine
* which module is generating the interrupt request. However, we can't do i2c
* transactions in interrupt context, so we must defer that work to a kernel
* thread. All we do here is acknowledge and mask the interrupt and wakeup
* the kernel thread.
*/
static irqreturn_t handle_twl6030_pih(int irq, void *devid)
{
disable_irq_nosync(irq);
complete(devid);
return IRQ_HANDLED;
}
/*----------------------------------------------------------------------*/
static inline void activate_irq(int irq)
{
#ifdef CONFIG_ARM
/* ARM requires an extra step to clear IRQ_NOREQUEST, which it
* sets on behalf of every irq_chip. Also sets IRQ_NOPROBE.
*/
set_irq_flags(irq, IRQF_VALID);
#else
/* same effect on other architectures */
irq_set_noprobe(irq);
#endif
}
int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
{
int twl_irq = (int)irq_get_chip_data(d->irq);
return irq_set_irq_wake(twl_irq, on);
}
/*----------------------------------------------------------------------*/
static unsigned twl6030_irq_next;
/*----------------------------------------------------------------------*/
int twl6030_interrupt_unmask(u8 bit_mask, u8 offset)
{
int ret;
u8 unmask_value;
ret = twl_i2c_read_u8(TWL_MODULE_PIH, &unmask_value,
REG_INT_STS_A + offset);
unmask_value &= (~(bit_mask));
ret |= twl_i2c_write_u8(TWL_MODULE_PIH, unmask_value,
REG_INT_STS_A + offset); /* unmask INT_MSK_A/B/C */
return ret;
}
EXPORT_SYMBOL(twl6030_interrupt_unmask);
int twl6030_interrupt_mask(u8 bit_mask, u8 offset)
{
int ret;
u8 mask_value;
ret = twl_i2c_read_u8(TWL_MODULE_PIH, &mask_value,
REG_INT_STS_A + offset);
mask_value |= (bit_mask);
ret |= twl_i2c_write_u8(TWL_MODULE_PIH, mask_value,
REG_INT_STS_A + offset); /* mask INT_MSK_A/B/C */
return ret;
}
EXPORT_SYMBOL(twl6030_interrupt_mask);
int twl6030_mmc_card_detect_config(void)
{
int ret;
u8 reg_val = 0;
/* Unmasking the Card detect Interrupt line for MMC1 from Phoenix */
twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
REG_INT_MSK_LINE_B);
twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
REG_INT_MSK_STS_B);
/*
* Initially Configuring MMC_CTRL for receiving interrupts &
* Card status on TWL6030 for MMC1
*/
ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
if (ret < 0) {
pr_err("twl6030: Failed to read MMCCTRL, error %d\n", ret);
return ret;
}
reg_val &= ~VMMC_AUTO_OFF;
reg_val |= SW_FC;
ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val, TWL6030_MMCCTRL);
if (ret < 0) {
pr_err("twl6030: Failed to write MMCCTRL, error %d\n", ret);
return ret;
}
/* Configuring PullUp-PullDown register */
ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val,
TWL6030_CFG_INPUT_PUPD3);
if (ret < 0) {
pr_err("twl6030: Failed to read CFG_INPUT_PUPD3, error %d\n",
ret);
return ret;
}
reg_val &= ~(MMC_PU | MMC_PD);
ret = twl_i2c_write_u8(TWL6030_MODULE_ID0, reg_val,
TWL6030_CFG_INPUT_PUPD3);
if (ret < 0) {
pr_err("twl6030: Failed to write CFG_INPUT_PUPD3, error %d\n",
ret);
return ret;
}
return 0;
}
EXPORT_SYMBOL(twl6030_mmc_card_detect_config);
int twl6030_mmc_card_detect(struct device *dev, int slot)
{
int ret = -EIO;
u8 read_reg = 0;
struct platform_device *pdev = to_platform_device(dev);
if (pdev->id) {
/* TWL6030 provide's Card detect support for
* only MMC1 controller.
*/
pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
return ret;
}
/*
* BIT0 of MMC_CTRL on TWL6030 provides card status for MMC1
* 0 - Card not present ,1 - Card present
*/
ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &read_reg,
TWL6030_MMCCTRL);
if (ret >= 0)
ret = read_reg & STS_MMC;
return ret;
}
EXPORT_SYMBOL(twl6030_mmc_card_detect);
int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
{
int status = 0;
int i;
struct task_struct *task;
int ret;
u8 mask[4];
static struct irq_chip twl6030_irq_chip;
mask[1] = 0xFF;
mask[2] = 0xFF;
mask[3] = 0xFF;
ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
REG_INT_MSK_LINE_A, 3); /* MASK ALL INT LINES */
ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
REG_INT_MSK_STS_A, 3); /* MASK ALL INT STS */
ret = twl_i2c_write(TWL_MODULE_PIH, &mask[0],
REG_INT_STS_A, 3); /* clear INT_STS_A,B,C */
twl6030_irq_base = irq_base;
/* install an irq handler for each of the modules;
* clone dummy irq_chip since PIH can't *do* anything
*/
twl6030_irq_chip = dummy_irq_chip;
twl6030_irq_chip.name = "twl6030";
twl6030_irq_chip.irq_set_type = NULL;
twl6030_irq_chip.irq_set_wake = twl6030_irq_set_wake;
for (i = irq_base; i < irq_end; i++) {
irq_set_chip_and_handler(i, &twl6030_irq_chip,
handle_simple_irq);
irq_set_chip_data(i, (void *)irq_num);
activate_irq(i);
}
twl6030_irq_next = i;
pr_info("twl6030: %s (irq %d) chaining IRQs %d..%d\n", "PIH",
irq_num, irq_base, twl6030_irq_next - 1);
/* install an irq handler to demultiplex the TWL6030 interrupt */
init_completion(&irq_event);
status = request_irq(irq_num, handle_twl6030_pih, IRQF_DISABLED,
"TWL6030-PIH", &irq_event);
if (status < 0) {
pr_err("twl6030: could not claim irq%d: %d\n", irq_num, status);
goto fail_irq;
}
task = kthread_run(twl6030_irq_thread, (void *)irq_num, "twl6030-irq");
if (IS_ERR(task)) {
pr_err("twl6030: could not create irq %d thread!\n", irq_num);
status = PTR_ERR(task);
goto fail_kthread;
}
return status;
fail_kthread:
free_irq(irq_num, &irq_event);
fail_irq:
for (i = irq_base; i < irq_end; i++)
irq_set_chip_and_handler(i, NULL, NULL);
return status;
}
int twl6030_exit_irq(void)
{
if (twl6030_irq_base) {
pr_err("twl6030: can't yet clean up IRQs?\n");
return -ENOSYS;
}
return 0;
}