Commit 1ce21f1c authored by David Brownell's avatar David Brownell Committed by Tony Lindgren

new twl4030 SIH irq init

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: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent c120ea2c
......@@ -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.
/*
* 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
*/
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;
};
/* Linux could (eventually) use either IRQ line */
static int irq_line;
/* TWL4030 INT module interrupt mask registers */
static const u8 __initconst twl4030_int_imr_regs[] = {
TWL4030_INT_PWR_IMR1,
TWL4030_INT_PWR_IMR2,
};
struct sih {
char name[8];
u8 module; /* module id */
u8 control_offset; /* for SIH_CTRL */
bool set_cor;
/* TWL4030 INT module interrupt status registers */
static const u8 __initconst twl4030_int_isr_regs[] = {
TWL4030_INT_PWR_ISR1,
TWL4030_INT_PWR_ISR2,
};
u8 bits; /* valid in isr/imr */
u8 bytes_ixr; /* bytelen of ISR/IMR/SIR */
/* 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,
};
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,
};
/* 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,
#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, \
}, },
/* 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
/* 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,
}, },
},
[1] = {
.name = "keypad",
.set_cor = true,
SIH_INITIALIZER(KEYPAD_KEYP, 4)
},
{
.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,
[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_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,
[3] = {
.name = "madc",
SIH_INITIALIZER(MADC, 4)
},
{
.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,
[4] = {
/* USB doesn't use the same SIH organization */
.name = "usb",
},
{
.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,
[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_irq_thread(long irq)
/*----------------------------------------------------------------------*/
/**
* 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;
const struct sih *sih;
u8 buf[4];
int i;
int status;
return (cor) ? twl4030_i2c_read_u8(mod_no, &tmp, reg) :
twl4030_i2c_write_u8(mod_no, 0xff, reg);
}
/* line 0 == int1_n signal; line 1 == int2_n signal */
if (line > 1)
return -EINVAL;
/**
* 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;
irq_line = line;
WARN_ON(twl4030_i2c_read_u8(mod_no, &tmp, reg) < 0);
/* disable all interrupts on our line */
memset(buf, 0xff, sizeof buf);
sih = sih_modules;
for (i = 0; i < ARRAY_SIZE(sih_modules); i++, sih++) {
tmp &= TWL4030_SIH_CTRL_COR_MASK;
tmp >>= __ffs(TWL4030_SIH_CTRL_COR_MASK);
/* skip USB -- it's funky */
if (!sih->bytes_ixr)
continue;
return tmp;
}
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");
/**
* 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)
/* Maybe disable "exclusive" mode; buffer second pending irq;
* set Clear-On-Read (COR) bit.
*
* 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.
* 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...
*/
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);
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");
}
}
for (j = 0; j < tmr.reg_cnt; j++) {
sih = sih_modules;
for (i = 0; i < ARRAY_SIZE(sih_modules); i++, sih++) {
u8 rxbuf[4];
int j;
/* Mask interrupts at the TWL4030 */
WARN_ON(twl4030_i2c_write_u8(tmr.mod_no, 0xff,
tmr.imrs[j]) < 0);
/* skip USB */
if (!sih->bytes_ixr)
continue;
/* Clear TWL4030 ISRs */
WARN_ON(twl4030_i2c_clear_isr(tmr.mod_no,
tmr.isrs[j], cor) < 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");
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 irq_base, unsigned irq_end)
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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