From: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Split the IRQ support out of twl4030-core.c into twl4030-irq.c,
including some minor tidy-ups and a note_interrupt() paranoia
in case of flakiness with some PIH interrupt.
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/mfd/Makefile | 2
drivers/mfd/twl4030-core.c | 412 +------------------------------------------
drivers/mfd/twl4030-irq.c | 408 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 420 insertions(+), 402 deletions(-)
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -12,7 +12,7 @@ obj-$(CONFIG_MFD_T7L66XB) += t7l66xb.o
obj-$(CONFIG_MFD_TC6387XB) += tc6387xb.o
obj-$(CONFIG_MFD_TC6393XB) += tc6393xb.o
-obj-$(CONFIG_TWL4030_CORE) += twl4030-core.o
+obj-$(CONFIG_TWL4030_CORE) += twl4030-core.o twl4030-irq.o
obj-$(CONFIG_MFD_CORE) += mfd-core.o
--- a/drivers/mfd/twl4030-core.c
+++ b/drivers/mfd/twl4030-core.c
@@ -27,15 +27,11 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
-#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/mutex.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
-#include <linux/random.h>
-#include <linux/kthread.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
+#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/i2c/twl4030.h>
@@ -93,26 +89,6 @@
#define twl_has_usb() false
#endif
-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 */
- set_irq_noprobe(irq);
-#endif
-}
-
-/* Primary Interrupt Handler on TWL4030 Registers */
-
-/* Register Definitions */
-
-#define REG_PIH_ISR_P1 (0x1)
-#define REG_PIH_ISR_P2 (0x2)
-#define REG_PIH_SIR (0x3)
/* Triton Core internal information (BEGIN) */
@@ -175,138 +151,6 @@ static inline void activate_irq(int irq)
/*----------------------------------------------------------------------*/
-/**
- * struct twl4030_mod_iregs - TWL module IMR/ISR regs to mask/clear at init
- * @mod_no: TWL4030 module number (e.g., TWL4030_MODULE_GPIO)
- * @sih_ctrl: address of module SIH_CTRL register
- * @reg_cnt: number of IMR/ISR regs
- * @imrs: pointer to array of TWL module interrupt mask register indices
- * @isrs: pointer to array of TWL module interrupt status register indices
- *
- * Ties together TWL4030 modules and lists of IMR/ISR registers to mask/clear
- * during twl_init_irq().
- */
-struct twl4030_mod_iregs {
- const u8 mod_no;
- const u8 sih_ctrl;
- const u8 reg_cnt;
- const u8 *imrs;
- const u8 *isrs;
-};
-
-/* TWL4030 INT module interrupt mask registers */
-static const u8 __initconst twl4030_int_imr_regs[] = {
- TWL4030_INT_PWR_IMR1,
- TWL4030_INT_PWR_IMR2,
-};
-
-/* TWL4030 INT module interrupt status registers */
-static const u8 __initconst twl4030_int_isr_regs[] = {
- TWL4030_INT_PWR_ISR1,
- TWL4030_INT_PWR_ISR2,
-};
-
-/* TWL4030 INTERRUPTS module interrupt mask registers */
-static const u8 __initconst twl4030_interrupts_imr_regs[] = {
- TWL4030_INTERRUPTS_BCIIMR1A,
- TWL4030_INTERRUPTS_BCIIMR1B,
- TWL4030_INTERRUPTS_BCIIMR2A,
- TWL4030_INTERRUPTS_BCIIMR2B,
-};
-
-/* TWL4030 INTERRUPTS module interrupt status registers */
-static const u8 __initconst twl4030_interrupts_isr_regs[] = {
- TWL4030_INTERRUPTS_BCIISR1A,
- TWL4030_INTERRUPTS_BCIISR1B,
- TWL4030_INTERRUPTS_BCIISR2A,
- TWL4030_INTERRUPTS_BCIISR2B,
-};
-
-/* TWL4030 MADC module interrupt mask registers */
-static const u8 __initconst twl4030_madc_imr_regs[] = {
- TWL4030_MADC_IMR1,
- TWL4030_MADC_IMR2,
-};
-
-/* TWL4030 MADC module interrupt status registers */
-static const u8 __initconst twl4030_madc_isr_regs[] = {
- TWL4030_MADC_ISR1,
- TWL4030_MADC_ISR2,
-};
-
-/* TWL4030 keypad module interrupt mask registers */
-static const u8 __initconst twl4030_keypad_imr_regs[] = {
- TWL4030_KEYPAD_KEYP_IMR1,
- TWL4030_KEYPAD_KEYP_IMR2,
-};
-
-/* TWL4030 keypad module interrupt status registers */
-static const u8 __initconst twl4030_keypad_isr_regs[] = {
- TWL4030_KEYPAD_KEYP_ISR1,
- TWL4030_KEYPAD_KEYP_ISR2,
-};
-
-/* TWL4030 GPIO module interrupt mask registers */
-static const u8 __initconst twl4030_gpio_imr_regs[] = {
- REG_GPIO_IMR1A,
- REG_GPIO_IMR1B,
- REG_GPIO_IMR2A,
- REG_GPIO_IMR2B,
- REG_GPIO_IMR3A,
- REG_GPIO_IMR3B,
-};
-
-/* TWL4030 GPIO module interrupt status registers */
-static const u8 __initconst twl4030_gpio_isr_regs[] = {
- REG_GPIO_ISR1A,
- REG_GPIO_ISR1B,
- REG_GPIO_ISR2A,
- REG_GPIO_ISR2B,
- REG_GPIO_ISR3A,
- REG_GPIO_ISR3B,
-};
-
-/* TWL4030 modules that have IMR/ISR registers that must be masked/cleared */
-static const struct twl4030_mod_iregs __initconst twl4030_mod_regs[] = {
- {
- .mod_no = TWL4030_MODULE_INT,
- .sih_ctrl = TWL4030_INT_PWR_SIH_CTRL,
- .reg_cnt = ARRAY_SIZE(twl4030_int_imr_regs),
- .imrs = twl4030_int_imr_regs,
- .isrs = twl4030_int_isr_regs,
- },
- {
- .mod_no = TWL4030_MODULE_INTERRUPTS,
- .sih_ctrl = TWL4030_INTERRUPTS_BCISIHCTRL,
- .reg_cnt = ARRAY_SIZE(twl4030_interrupts_imr_regs),
- .imrs = twl4030_interrupts_imr_regs,
- .isrs = twl4030_interrupts_isr_regs,
- },
- {
- .mod_no = TWL4030_MODULE_MADC,
- .sih_ctrl = TWL4030_MADC_SIH_CTRL,
- .reg_cnt = ARRAY_SIZE(twl4030_madc_imr_regs),
- .imrs = twl4030_madc_imr_regs,
- .isrs = twl4030_madc_isr_regs,
- },
- {
- .mod_no = TWL4030_MODULE_KEYPAD,
- .sih_ctrl = TWL4030_KEYPAD_KEYP_SIH_CTRL,
- .reg_cnt = ARRAY_SIZE(twl4030_keypad_imr_regs),
- .imrs = twl4030_keypad_imr_regs,
- .isrs = twl4030_keypad_isr_regs,
- },
- {
- .mod_no = TWL4030_MODULE_GPIO,
- .sih_ctrl = REG_GPIO_SIH_CTRL,
- .reg_cnt = ARRAY_SIZE(twl4030_gpio_imr_regs),
- .imrs = twl4030_gpio_imr_regs,
- .isrs = twl4030_gpio_isr_regs,
- },
-};
-
-/*----------------------------------------------------------------*/
-
/* is driver active, bound to a chip? */
static bool inuse;
@@ -367,33 +211,6 @@ static struct twl4030mapping twl4030_map
/*----------------------------------------------------------------------*/
-/*
- * TWL4030 doesn't have PIH mask, hence dummy function for mask
- * and unmask of the (eight) interrupts reported at that level ...
- * masking is only available from SIH (secondary) modules.
- */
-
-static void twl4030_i2c_ackirq(unsigned int irq)
-{
-}
-
-static void twl4030_i2c_disableint(unsigned int irq)
-{
-}
-
-static void twl4030_i2c_enableint(unsigned int irq)
-{
-}
-
-static struct irq_chip twl4030_irq_chip = {
- .name = "twl4030",
- .ack = twl4030_i2c_ackirq,
- .mask = twl4030_i2c_disableint,
- .unmask = twl4030_i2c_enableint,
-};
-
-/*----------------------------------------------------------------------*/
-
/* Exported Functions */
/**
@@ -535,109 +352,6 @@ EXPORT_SYMBOL(twl4030_i2c_read_u8);
/*----------------------------------------------------------------------*/
-static unsigned twl4030_irq_base;
-
-static struct completion irq_event;
-
-/*
- * This thread processes interrupts reported by the Primary Interrupt Handler.
- */
-static int twl4030_irq_thread(void *data)
-{
- long irq = (long)data;
- irq_desc_t *desc = irq_desc + irq;
- static unsigned i2c_errors;
- const static unsigned max_i2c_errors = 100;
-
- current->flags |= PF_NOFREEZE;
-
- while (!kthread_should_stop()) {
- int ret;
- int module_irq;
- u8 pih_isr;
-
- /* Wait for IRQ, then read PIH irq status (also blocking) */
- wait_for_completion_interruptible(&irq_event);
-
- ret = twl4030_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
- REG_PIH_ISR_P1);
- if (ret) {
- pr_warning("%s: I2C error %d reading PIH ISR\n",
- DRIVER_NAME, ret);
- if (++i2c_errors >= max_i2c_errors) {
- printk(KERN_ERR "Maximum I2C error count"
- " exceeded. Terminating %s.\n",
- __func__);
- break;
- }
- complete(&irq_event);
- continue;
- }
-
- /* these handlers deal with the relevant SIH irq status */
- local_irq_disable();
- for (module_irq = twl4030_irq_base;
- pih_isr;
- pih_isr >>= 1, module_irq++) {
- if (pih_isr & 0x1) {
- irq_desc_t *d = irq_desc + module_irq;
-
- d->handle_irq(module_irq, d);
- }
- }
- local_irq_enable();
-
- desc->chip->unmask(irq);
- }
-
- return 0;
-}
-
-/*
- * do_twl4030_irq() is the desc->handle method for the twl4030 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 twl4030 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 void do_twl4030_irq(unsigned int irq, irq_desc_t *desc)
-{
- const unsigned int cpu = smp_processor_id();
-
- /*
- * Earlier this was desc->triggered = 1;
- */
- desc->status |= IRQ_LEVEL;
-
- /*
- * Acknowledge, clear _AND_ disable the interrupt.
- */
- desc->chip->ack(irq);
-
- if (!desc->depth) {
- kstat_cpu(cpu).irqs[irq]++;
-
- complete(&irq_event);
- }
-}
-
-static struct task_struct * __init start_twl4030_irq_thread(long irq)
-{
- struct task_struct *thread;
-
- init_completion(&irq_event);
- thread = kthread_run(twl4030_irq_thread, (void *)irq, "twl4030-irq");
- if (!thread)
- pr_err("%s: could not create twl4030 irq %ld thread!\n",
- DRIVER_NAME, irq);
-
- return thread;
-}
-
-/*----------------------------------------------------------------------*/
-
static int add_children(struct twl4030_platform_data *pdata)
{
struct platform_device *pdev = NULL;
@@ -965,123 +679,17 @@ static void __init clocks_init(void)
/*----------------------------------------------------------------------*/
-/**
- * twl4030_i2c_clear_isr - clear TWL4030 SIH ISR regs via read + write
- * @mod_no: TWL4030 module number
- * @reg: register index to clear
- * @cor: value of the <module>_SIH_CTRL.COR bit (1 or 0)
- *
- * Either reads (cor == 1) or writes (cor == 0) to a TWL4030 interrupt
- * status register to ensure that any prior interrupts are cleared.
- * Returns the status from the I2C read operation.
- */
-static int __init twl4030_i2c_clear_isr(u8 mod_no, u8 reg, u8 cor)
-{
- u8 tmp;
-
- return (cor) ? twl4030_i2c_read_u8(mod_no, &tmp, reg) :
- twl4030_i2c_write_u8(mod_no, 0xff, reg);
-}
-
-/**
- * twl4030_read_cor_bit - are TWL module ISRs cleared by reads or writes?
- * @mod_no: TWL4030 module number
- * @reg: register index to clear
- *
- * Returns 1 if the TWL4030 SIH interrupt status registers (ISRs) for
- * the specified TWL module are cleared by reads, or 0 if cleared by
- * writes.
- */
-static int twl4030_read_cor_bit(u8 mod_no, u8 reg)
-{
- u8 tmp = 0;
-
- WARN_ON(twl4030_i2c_read_u8(mod_no, &tmp, reg) < 0);
-
- tmp &= TWL4030_SIH_CTRL_COR_MASK;
- tmp >>= __ffs(TWL4030_SIH_CTRL_COR_MASK);
-
- return tmp;
-}
-
-/**
- * twl4030_mask_clear_intrs - mask and clear all TWL4030 interrupts
- * @t: pointer to twl4030_mod_iregs array
- * @t_sz: ARRAY_SIZE(t) (starting at 1)
- *
- * Mask all TWL4030 interrupt mask registers (IMRs) and clear all
- * interrupt status registers (ISRs). No return value, but will WARN if
- * any I2C operations fail.
- */
-static void __init twl4030_mask_clear_intrs(const struct twl4030_mod_iregs *t,
- const u8 t_sz)
-{
- int i, j;
-
- /*
- * N.B. - further efficiency is possible here. Eight I2C
- * operations on BCI and GPIO modules are avoidable if I2C
- * burst read/write transactions were implemented. Would
- * probably save about 1ms of boot time and a small amount of
- * power.
- */
- for (i = 0; i < t_sz; i++) {
- const struct twl4030_mod_iregs tmr = t[i];
- int cor;
-
- /* Are ISRs cleared by reads or writes? */
- cor = twl4030_read_cor_bit(tmr.mod_no, tmr.sih_ctrl);
-
- for (j = 0; j < tmr.reg_cnt; j++) {
-
- /* Mask interrupts at the TWL4030 */
- WARN_ON(twl4030_i2c_write_u8(tmr.mod_no, 0xff,
- tmr.imrs[j]) < 0);
-
- /* Clear TWL4030 ISRs */
- WARN_ON(twl4030_i2c_clear_isr(tmr.mod_no,
- tmr.isrs[j], cor) < 0);
- }
- }
-}
-
-
-static void twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
-{
- int i;
-
- /*
- * Mask and clear all TWL4030 interrupts since initially we do
- * not have any TWL4030 module interrupt handlers present
- */
- twl4030_mask_clear_intrs(twl4030_mod_regs,
- ARRAY_SIZE(twl4030_mod_regs));
-
- twl4030_irq_base = irq_base;
-
- /* install an irq handler for each of the PIH modules */
- for (i = irq_base; i < irq_end; i++) {
- set_irq_chip_and_handler(i, &twl4030_irq_chip,
- handle_simple_irq);
- activate_irq(i);
- }
-
- /* install an irq handler to demultiplex the TWL4030 interrupt */
- set_irq_data(irq_num, start_twl4030_irq_thread(irq_num));
- set_irq_chained_handler(irq_num, do_twl4030_irq);
-}
-
-/*----------------------------------------------------------------------*/
+int twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end);
+int twl_exit_irq(void);
static int twl4030_remove(struct i2c_client *client)
{
unsigned i;
+ int status;
- /* FIXME undo twl_init_irq() */
- if (twl4030_irq_base) {
- dev_err(&client->dev, "can't yet clean up IRQs?\n");
- return -ENOSYS;
- }
+ status = twl_exit_irq();
+ if (status < 0)
+ return status;
for (i = 0; i < TWL4030_NUM_SLAVES; i++) {
struct twl4030_client *twl = &twl4030_modules[i];
@@ -1112,7 +720,7 @@ twl4030_probe(struct i2c_client *client,
return -EIO;
}
- if (inuse || twl4030_irq_base) {
+ if (inuse) {
dev_dbg(&client->dev, "driver is already in use\n");
return -EBUSY;
}
@@ -1146,7 +754,9 @@ twl4030_probe(struct i2c_client *client,
if (client->irq
&& pdata->irq_base
&& pdata->irq_end > pdata->irq_base) {
- twl_init_irq(client->irq, pdata->irq_base, pdata->irq_end);
+ status = twl_init_irq(client->irq, pdata->irq_base, pdata->irq_end);
+ if (status < 0)
+ goto fail;
dev_info(&client->dev, "IRQ %d chains IRQs %d..%d\n",
client->irq, pdata->irq_base, pdata->irq_end - 1);
}
--- /dev/null
+++ b/drivers/mfd/twl4030-irq.c
@@ -0,0 +1,408 @@
+/*
+ * twl4030-irq.c - TWL4030/TPS659x0 irq support
+ *
+ * Copyright (C) 2005-2006 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@xxxxxxxxx>
+ *
+ * Code cleanup and modifications to IRQ handler.
+ * by syed khasim <x0khasim@xxxxxx>
+ *
+ * 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/twl4030.h>
+
+
+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 */
+ set_irq_noprobe(irq);
+#endif
+}
+
+/* PIH register offsets */
+#define REG_PIH_ISR_P1 0x01
+#define REG_PIH_ISR_P2 0x02
+#define REG_PIH_SIR 0x03 /* for testing */
+
+/*----------------------------------------------------------------------*/
+
+/**
+ * struct twl4030_mod_iregs - TWL module IMR/ISR regs to mask/clear at init
+ * @mod_no: TWL4030 module number (e.g., TWL4030_MODULE_GPIO)
+ * @sih_ctrl: address of module SIH_CTRL register
+ * @reg_cnt: number of IMR/ISR regs
+ * @imrs: pointer to array of TWL module interrupt mask register indices
+ * @isrs: pointer to array of TWL module interrupt status register indices
+ *
+ * Ties together TWL4030 modules and lists of IMR/ISR registers to mask/clear
+ * during twl_init_irq().
+ */
+struct twl4030_mod_iregs {
+ const u8 mod_no;
+ const u8 sih_ctrl;
+ const u8 reg_cnt;
+ const u8 *imrs;
+ const u8 *isrs;
+};
+
+/* TWL4030 INT module interrupt mask registers */
+static const u8 __initconst twl4030_int_imr_regs[] = {
+ TWL4030_INT_PWR_IMR1,
+ TWL4030_INT_PWR_IMR2,
+};
+
+/* TWL4030 INT module interrupt status registers */
+static const u8 __initconst twl4030_int_isr_regs[] = {
+ TWL4030_INT_PWR_ISR1,
+ TWL4030_INT_PWR_ISR2,
+};
+
+/* TWL4030 INTERRUPTS module interrupt mask registers */
+static const u8 __initconst twl4030_interrupts_imr_regs[] = {
+ TWL4030_INTERRUPTS_BCIIMR1A,
+ TWL4030_INTERRUPTS_BCIIMR1B,
+ TWL4030_INTERRUPTS_BCIIMR2A,
+ TWL4030_INTERRUPTS_BCIIMR2B,
+};
+
+/* TWL4030 INTERRUPTS module interrupt status registers */
+static const u8 __initconst twl4030_interrupts_isr_regs[] = {
+ TWL4030_INTERRUPTS_BCIISR1A,
+ TWL4030_INTERRUPTS_BCIISR1B,
+ TWL4030_INTERRUPTS_BCIISR2A,
+ TWL4030_INTERRUPTS_BCIISR2B,
+};
+
+/* TWL4030 MADC module interrupt mask registers */
+static const u8 __initconst twl4030_madc_imr_regs[] = {
+ TWL4030_MADC_IMR1,
+ TWL4030_MADC_IMR2,
+};
+
+/* TWL4030 MADC module interrupt status registers */
+static const u8 __initconst twl4030_madc_isr_regs[] = {
+ TWL4030_MADC_ISR1,
+ TWL4030_MADC_ISR2,
+};
+
+/* TWL4030 keypad module interrupt mask registers */
+static const u8 __initconst twl4030_keypad_imr_regs[] = {
+ TWL4030_KEYPAD_KEYP_IMR1,
+ TWL4030_KEYPAD_KEYP_IMR2,
+};
+
+/* TWL4030 keypad module interrupt status registers */
+static const u8 __initconst twl4030_keypad_isr_regs[] = {
+ TWL4030_KEYPAD_KEYP_ISR1,
+ TWL4030_KEYPAD_KEYP_ISR2,
+};
+
+/* TWL4030 GPIO module interrupt mask registers */
+static const u8 __initconst twl4030_gpio_imr_regs[] = {
+ REG_GPIO_IMR1A,
+ REG_GPIO_IMR1B,
+ REG_GPIO_IMR2A,
+ REG_GPIO_IMR2B,
+ REG_GPIO_IMR3A,
+ REG_GPIO_IMR3B,
+};
+
+/* TWL4030 GPIO module interrupt status registers */
+static const u8 __initconst twl4030_gpio_isr_regs[] = {
+ REG_GPIO_ISR1A,
+ REG_GPIO_ISR1B,
+ REG_GPIO_ISR2A,
+ REG_GPIO_ISR2B,
+ REG_GPIO_ISR3A,
+ REG_GPIO_ISR3B,
+};
+
+/* TWL4030 modules that have IMR/ISR registers that must be masked/cleared */
+static const struct twl4030_mod_iregs __initconst twl4030_mod_regs[] = {
+ {
+ .mod_no = TWL4030_MODULE_INT,
+ .sih_ctrl = TWL4030_INT_PWR_SIH_CTRL,
+ .reg_cnt = ARRAY_SIZE(twl4030_int_imr_regs),
+ .imrs = twl4030_int_imr_regs,
+ .isrs = twl4030_int_isr_regs,
+ },
+ {
+ .mod_no = TWL4030_MODULE_INTERRUPTS,
+ .sih_ctrl = TWL4030_INTERRUPTS_BCISIHCTRL,
+ .reg_cnt = ARRAY_SIZE(twl4030_interrupts_imr_regs),
+ .imrs = twl4030_interrupts_imr_regs,
+ .isrs = twl4030_interrupts_isr_regs,
+ },
+ {
+ .mod_no = TWL4030_MODULE_MADC,
+ .sih_ctrl = TWL4030_MADC_SIH_CTRL,
+ .reg_cnt = ARRAY_SIZE(twl4030_madc_imr_regs),
+ .imrs = twl4030_madc_imr_regs,
+ .isrs = twl4030_madc_isr_regs,
+ },
+ {
+ .mod_no = TWL4030_MODULE_KEYPAD,
+ .sih_ctrl = TWL4030_KEYPAD_KEYP_SIH_CTRL,
+ .reg_cnt = ARRAY_SIZE(twl4030_keypad_imr_regs),
+ .imrs = twl4030_keypad_imr_regs,
+ .isrs = twl4030_keypad_isr_regs,
+ },
+ {
+ .mod_no = TWL4030_MODULE_GPIO,
+ .sih_ctrl = REG_GPIO_SIH_CTRL,
+ .reg_cnt = ARRAY_SIZE(twl4030_gpio_imr_regs),
+ .imrs = twl4030_gpio_imr_regs,
+ .isrs = twl4030_gpio_isr_regs,
+ },
+};
+
+/*----------------------------------------------------------------------*/
+
+static unsigned twl4030_irq_base;
+
+static struct completion irq_event;
+
+/*
+ * This thread processes interrupts reported by the Primary Interrupt Handler.
+ */
+static int twl4030_irq_thread(void *data)
+{
+ long irq = (long)data;
+ irq_desc_t *desc = irq_desc + irq;
+ static unsigned i2c_errors;
+ const static unsigned max_i2c_errors = 100;
+
+ current->flags |= PF_NOFREEZE;
+
+ while (!kthread_should_stop()) {
+ int ret;
+ int module_irq;
+ u8 pih_isr;
+
+ /* Wait for IRQ, then read PIH irq status (also blocking) */
+ wait_for_completion_interruptible(&irq_event);
+
+ ret = twl4030_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
+ REG_PIH_ISR_P1);
+ if (ret) {
+ pr_warning("twl4030: 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;
+ }
+
+ /* these handlers deal with the relevant SIH irq status */
+ local_irq_disable();
+ for (module_irq = twl4030_irq_base;
+ pih_isr;
+ pih_isr >>= 1, module_irq++) {
+ if (pih_isr & 0x1) {
+ irq_desc_t *d = irq_desc + module_irq;
+
+ /* These can't be masked ... always warn
+ * if we get any surprises.
+ */
+ if (d->status & IRQ_DISABLED)
+ note_interrupt(module_irq, d,
+ IRQ_NONE);
+ else
+ d->handle_irq(module_irq, d);
+ }
+ }
+ local_irq_enable();
+
+ desc->chip->unmask(irq);
+ }
+
+ return 0;
+}
+
+/*
+ * handle_twl4030_pih() is the desc->handle method for the twl4030 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 twl4030 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 void handle_twl4030_pih(unsigned int irq, irq_desc_t *desc)
+{
+ /* Acknowledge, clear *AND* mask the interrupt... */
+ desc->chip->ack(irq);
+ complete(&irq_event);
+}
+
+static struct task_struct *start_twl4030_irq_thread(long irq)
+{
+ struct task_struct *thread;
+
+ init_completion(&irq_event);
+ thread = kthread_run(twl4030_irq_thread, (void *)irq, "twl4030-irq");
+ if (!thread)
+ pr_err("twl4030: could not create irq %ld thread!\n", irq);
+
+ return thread;
+}
+
+/*----------------------------------------------------------------------*/
+
+/**
+ * twl4030_i2c_clear_isr - clear TWL4030 SIH ISR regs via read + write
+ * @mod_no: TWL4030 module number
+ * @reg: register index to clear
+ * @cor: value of the <module>_SIH_CTRL.COR bit (1 or 0)
+ *
+ * Either reads (cor == 1) or writes (cor == 0) to a TWL4030 interrupt
+ * status register to ensure that any prior interrupts are cleared.
+ * Returns the status from the I2C read operation.
+ */
+static int __init twl4030_i2c_clear_isr(u8 mod_no, u8 reg, u8 cor)
+{
+ u8 tmp;
+
+ return (cor) ? twl4030_i2c_read_u8(mod_no, &tmp, reg) :
+ twl4030_i2c_write_u8(mod_no, 0xff, reg);
+}
+
+/**
+ * twl4030_read_cor_bit - are TWL module ISRs cleared by reads or writes?
+ * @mod_no: TWL4030 module number
+ * @reg: register index to clear
+ *
+ * Returns 1 if the TWL4030 SIH interrupt status registers (ISRs) for
+ * the specified TWL module are cleared by reads, or 0 if cleared by
+ * writes.
+ */
+static int twl4030_read_cor_bit(u8 mod_no, u8 reg)
+{
+ u8 tmp = 0;
+
+ WARN_ON(twl4030_i2c_read_u8(mod_no, &tmp, reg) < 0);
+
+ tmp &= TWL4030_SIH_CTRL_COR_MASK;
+ tmp >>= __ffs(TWL4030_SIH_CTRL_COR_MASK);
+
+ return tmp;
+}
+
+/**
+ * twl4030_mask_clear_intrs - mask and clear all TWL4030 interrupts
+ * @t: pointer to twl4030_mod_iregs array
+ * @t_sz: ARRAY_SIZE(t) (starting at 1)
+ *
+ * Mask all TWL4030 interrupt mask registers (IMRs) and clear all
+ * interrupt status registers (ISRs). No return value, but will WARN if
+ * any I2C operations fail.
+ */
+static void __init twl4030_mask_clear_intrs(const struct twl4030_mod_iregs *t,
+ const u8 t_sz)
+{
+ int i, j;
+
+ /*
+ * N.B. - further efficiency is possible here. Eight I2C
+ * operations on BCI and GPIO modules are avoidable if I2C
+ * burst read/write transactions were implemented. Would
+ * probably save about 1ms of boot time and a small amount of
+ * power.
+ */
+ for (i = 0; i < t_sz; i++) {
+ const struct twl4030_mod_iregs tmr = t[i];
+ int cor;
+
+ /* Are ISRs cleared by reads or writes? */
+ cor = twl4030_read_cor_bit(tmr.mod_no, tmr.sih_ctrl);
+
+ for (j = 0; j < tmr.reg_cnt; j++) {
+
+ /* Mask interrupts at the TWL4030 */
+ WARN_ON(twl4030_i2c_write_u8(tmr.mod_no, 0xff,
+ tmr.imrs[j]) < 0);
+
+ /* Clear TWL4030 ISRs */
+ WARN_ON(twl4030_i2c_clear_isr(tmr.mod_no,
+ tmr.isrs[j], cor) < 0);
+ }
+ }
+}
+
+
+int twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
+{
+ static struct irq_chip twl4030_irq_chip;
+
+ int i;
+
+ /*
+ * Mask and clear all TWL4030 interrupts since initially we do
+ * not have any TWL4030 module interrupt handlers present
+ */
+ twl4030_mask_clear_intrs(twl4030_mod_regs,
+ ARRAY_SIZE(twl4030_mod_regs));
+
+ twl4030_irq_base = irq_base;
+
+ /* install an irq handler for each of the SIH modules;
+ * clone dummy irq_chip since PIH can't *do* anything
+ */
+ twl4030_irq_chip = dummy_irq_chip;
+ twl4030_irq_chip.name = "twl4030";
+
+ for (i = irq_base; i < irq_end; i++) {
+ set_irq_chip_and_handler(i, &twl4030_irq_chip,
+ handle_simple_irq);
+ activate_irq(i);
+ }
+
+ /* install an irq handler to demultiplex the TWL4030 interrupt */
+ set_irq_data(irq_num, start_twl4030_irq_thread(irq_num));
+ set_irq_chained_handler(irq_num, handle_twl4030_pih);
+
+ return 0;
+}
+
+int twl_exit_irq(void)
+{
+ /* FIXME undo twl_init_irq() */
+ if (twl4030_irq_base) {
+ pr_err("twl4030: can't yet clean up IRQs?\n");
+ return -ENOSYS;
+ }
+ return 0;
+}
--
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