From: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Switch to a different twl4030-irq SIH irq init scheme. Its goal
is to remove some section issues while providing a data structure
that can be reused by generic SIH IRQ handling code.
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/mfd/twl4030-irq.c | 394 ++++++++++++++++++++++----------------------
1 file changed, 201 insertions(+), 193 deletions(-)
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c
@@ -35,156 +35,139 @@
#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
-}
+/*
+ * TWL4030 IRQ handling has two stages in hardware, and thus in software.
+ * The Primary Interrupt Handler (PIH) stage exposes status bits saying
+ * which Secondary Interrupt Handler (SIH) stage is raising an interrupt.
+ * SIH modules are more traditional IRQ components, which support per-IRQ
+ * enable/disable and trigger controls; they do most of the work.
+ *
+ * These chips are designed to support IRQ handling from two different
+ * I2C masters. Each has a dedicated IRQ line, and dedicated IRQ status
+ * and mask registers in the PIH and SIH modules.
+ *
+ * We set up IRQs starting at a platform-specified base, always starting
+ * with PIH and the SIH for PWR_INT and then usually adding GPIO:
+ * base + 0 .. base + 7 PIH
+ * base + 8 .. base + 15 SIH for PWR_INT
+ * base + 16 .. base + 33 SIH for GPIO
+ */
/* 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,
-};
+/* Linux could (eventually) use either IRQ line */
+static int irq_line;
-/* 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,
-};
+struct sih {
+ char name[8];
+ u8 module; /* module id */
+ u8 control_offset; /* for SIH_CTRL */
+ bool set_cor;
-/* TWL4030 MADC module interrupt mask registers */
-static const u8 __initconst twl4030_madc_imr_regs[] = {
- TWL4030_MADC_IMR1,
- TWL4030_MADC_IMR2,
-};
+ u8 bits; /* valid in isr/imr */
+ u8 bytes_ixr; /* bytelen of ISR/IMR/SIR */
-/* TWL4030 MADC module interrupt status registers */
-static const u8 __initconst twl4030_madc_isr_regs[] = {
- TWL4030_MADC_ISR1,
- TWL4030_MADC_ISR2,
-};
+ u8 edr_offset;
+ u8 bytes_edr; /* bytelen of EDR */
-/* TWL4030 keypad module interrupt mask registers */
-static const u8 __initconst twl4030_keypad_imr_regs[] = {
- TWL4030_KEYPAD_KEYP_IMR1,
- TWL4030_KEYPAD_KEYP_IMR2,
+ /* SIR ignored -- set interrupt, for testing only */
+ struct irq_data {
+ u8 isr_offset;
+ u8 imr_offset;
+ } mask[2];
+ /* + 2 bytes padding */
};
-/* TWL4030 keypad module interrupt status registers */
-static const u8 __initconst twl4030_keypad_isr_regs[] = {
- TWL4030_KEYPAD_KEYP_ISR1,
- TWL4030_KEYPAD_KEYP_ISR2,
-};
+#define SIH_INITIALIZER(modname, nbits) \
+ .module = TWL4030_MODULE_ ## modname, \
+ .control_offset = TWL4030_ ## modname ## _SIH_CTRL, \
+ .bits = nbits, \
+ .bytes_ixr = DIV_ROUND_UP(nbits, 8), \
+ .edr_offset = TWL4030_ ## modname ## _EDR, \
+ .bytes_edr = DIV_ROUND_UP((2*(nbits)), 8), \
+ .mask = { { \
+ .isr_offset = TWL4030_ ## modname ## _ISR1, \
+ .imr_offset = TWL4030_ ## modname ## _IMR1, \
+ }, \
+ { \
+ .isr_offset = TWL4030_ ## modname ## _ISR2, \
+ .imr_offset = TWL4030_ ## modname ## _IMR2, \
+ }, },
-/* 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,
-};
+/* register naming policies are inconsistent ... */
+#define TWL4030_INT_PWR_EDR TWL4030_INT_PWR_EDR1
+#define TWL4030_MODULE_KEYPAD_KEYP TWL4030_MODULE_KEYPAD
+#define TWL4030_MODULE_INT_PWR TWL4030_MODULE_INT
-/* 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,
+/* Order in this table matches order in PIH_ISR. That is,
+ * BIT(n) in PIH_ISR is sih_modules[n].
+ */
+static const struct sih sih_modules[6] = {
+ [0] = {
+ .name = "gpio",
+ .module = TWL4030_MODULE_GPIO,
+ .control_offset = REG_GPIO_SIH_CTRL,
+ .set_cor = true,
+ .bits = TWL4030_GPIO_MAX,
+ .bytes_ixr = 3,
+ /* Note: *all* of these IRQs default to no-trigger */
+ .edr_offset = REG_GPIO_EDR1,
+ .bytes_edr = 5,
+ .mask = { {
+ .isr_offset = REG_GPIO_ISR1A,
+ .imr_offset = REG_GPIO_IMR1A,
+ }, {
+ .isr_offset = REG_GPIO_ISR1B,
+ .imr_offset = REG_GPIO_IMR1B,
+ }, },
},
- {
- .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,
+ [1] = {
+ .name = "keypad",
+ .set_cor = true,
+ SIH_INITIALIZER(KEYPAD_KEYP, 4)
},
- {
- .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,
+ [2] = {
+ .name = "bci",
+ .module = TWL4030_MODULE_INTERRUPTS,
+ .control_offset = TWL4030_INTERRUPTS_BCISIHCTRL,
+ .bits = 12,
+ .bytes_ixr = 2,
+ .edr_offset = TWL4030_INTERRUPTS_BCIEDR1,
+ /* Note: most of these IRQs default to no-trigger */
+ .bytes_edr = 3,
+ .mask = { {
+ .isr_offset = TWL4030_INTERRUPTS_BCIISR1A,
+ .imr_offset = TWL4030_INTERRUPTS_BCIIMR1A,
+ }, {
+ .isr_offset = TWL4030_INTERRUPTS_BCIISR1B,
+ .imr_offset = TWL4030_INTERRUPTS_BCIIMR1B,
+ }, },
},
- {
- .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,
+ [3] = {
+ .name = "madc",
+ SIH_INITIALIZER(MADC, 4)
},
- {
- .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,
+ [4] = {
+ /* USB doesn't use the same SIH organization */
+ .name = "usb",
},
+ [5] = {
+ .name = "power",
+ .set_cor = true,
+ SIH_INITIALIZER(INT_PWR, 8)
+ },
+ /* there are no SIH modules #6 or #7 ... */
};
+#undef TWL4030_MODULE_KEYPAD_KEYP
+#undef TWL4030_MODULE_INT_PWR
+#undef TWL4030_INT_PWR_EDR
+
/*----------------------------------------------------------------------*/
static unsigned twl4030_irq_base;
@@ -282,99 +265,124 @@ static struct task_struct *start_twl4030
/*----------------------------------------------------------------------*/
-/**
- * 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)
+/*
+ * twl4030_init_sih_modules() ... start from a known state where no
+ * IRQs will be coming in, and where we can quickly enable them then
+ * handle them as they arrive. Mask all IRQs: maybe init SIH_CTRL.
*
- * 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.
+ * NOTE: we don't touch EDR registers here; they stay with hardware
+ * defaults or whatever the last value was. Note that when both EDR
+ * bits for an IRQ are clear, that's as if its IMR bit is set...
*/
-static int __init twl4030_i2c_clear_isr(u8 mod_no, u8 reg, u8 cor)
+static int twl4030_init_sih_modules(unsigned line)
{
- u8 tmp;
-
- return (cor) ? twl4030_i2c_read_u8(mod_no, &tmp, reg) :
- twl4030_i2c_write_u8(mod_no, 0xff, reg);
-}
+ const struct sih *sih;
+ u8 buf[4];
+ int i;
+ int status;
-/**
- * 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;
+ /* line 0 == int1_n signal; line 1 == int2_n signal */
+ if (line > 1)
+ return -EINVAL;
- WARN_ON(twl4030_i2c_read_u8(mod_no, &tmp, reg) < 0);
+ irq_line = line;
- tmp &= TWL4030_SIH_CTRL_COR_MASK;
- tmp >>= __ffs(TWL4030_SIH_CTRL_COR_MASK);
+ /* disable all interrupts on our line */
+ memset(buf, 0xff, sizeof buf);
+ sih = sih_modules;
+ for (i = 0; i < ARRAY_SIZE(sih_modules); i++, sih++) {
- return tmp;
-}
+ /* skip USB -- it's funky */
+ if (!sih->bytes_ixr)
+ continue;
-/**
- * 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;
+ status = twl4030_i2c_write(sih->module, buf,
+ sih->mask[line].imr_offset, sih->bytes_ixr);
+ if (status < 0)
+ pr_err("twl4030: err %d initializing %s %s\n",
+ status, sih->name, "IMR");
- /*
- * 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;
+ /* Maybe disable "exclusive" mode; buffer second pending irq;
+ * set Clear-On-Read (COR) bit.
+ *
+ * NOTE that sometimes COR polarity is documented as being
+ * inverted: for MADC and BCI, COR=1 means "clear on write".
+ * And for PWR_INT it's not documented...
+ */
+ if (sih->set_cor) {
+ status = twl4030_i2c_write_u8(sih->module,
+ TWL4030_SIH_CTRL_COR_MASK,
+ sih->control_offset);
+ if (status < 0)
+ pr_err("twl4030: err %d initializing %s %s\n",
+ status, sih->name, "SIH_CTRL");
+ }
+ }
- /* Are ISRs cleared by reads or writes? */
- cor = twl4030_read_cor_bit(tmr.mod_no, tmr.sih_ctrl);
+ sih = sih_modules;
+ for (i = 0; i < ARRAY_SIZE(sih_modules); i++, sih++) {
+ u8 rxbuf[4];
+ int j;
- for (j = 0; j < tmr.reg_cnt; j++) {
+ /* skip USB */
+ if (!sih->bytes_ixr)
+ continue;
- /* Mask interrupts at the TWL4030 */
- WARN_ON(twl4030_i2c_write_u8(tmr.mod_no, 0xff,
- tmr.imrs[j]) < 0);
+ /* Clear pending interrupt status. Either the read was
+ * enough, or we need to write those bits. Repeat, in
+ * case an IRQ is pending (PENDDIS=0) ... that's not
+ * uncommon with PWR_INT.PWRON.
+ */
+ for (j = 0; j < 2; j++) {
+ status = twl4030_i2c_read(sih->module, rxbuf,
+ sih->mask[line].isr_offset, sih->bytes_ixr);
+ if (status < 0)
+ pr_err("twl4030: err %d initializing %s %s\n",
+ status, sih->name, "ISR");
- /* Clear TWL4030 ISRs */
- WARN_ON(twl4030_i2c_clear_isr(tmr.mod_no,
- tmr.isrs[j], cor) < 0);
+ if (!sih->set_cor)
+ status = twl4030_i2c_write(sih->module, buf,
+ sih->mask[line].isr_offset,
+ sih->bytes_ixr);
+ /* else COR=1 means read sufficed.
+ * (for most SIH modules...)
+ */
}
}
+
+ return 0;
+}
+
+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
}
+/* FIXME pass in which interrupt line we'll use ... */
+#define twl_irq_line 0
int twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
{
static struct irq_chip twl4030_irq_chip;
+ int status;
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));
+ status = twl4030_init_sih_modules(twl_irq_line);
+ if (status < 0)
+ return status;
twl4030_irq_base = irq_base;
@@ -394,7 +402,7 @@ int twl_init_irq(int irq_num, unsigned i
set_irq_data(irq_num, start_twl4030_irq_thread(irq_num));
set_irq_chained_handler(irq_num, handle_twl4030_pih);
- return 0;
+ return status;
}
int twl_exit_irq(void)
--
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