From 2fb07a10e0aa699ddb12aba1459208579bdc9802 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Tue, 23 Jun 2015 11:15:10 -0500 Subject: [PATCH] rtc: ds1307: Convert to threaded IRQ The driver currently emulates the concept of threaded IRQ using a workqueue, which it really does not need to. Instead, switch over to threaded_irq handlers which is meant precisely for the same purpose. Signed-off-by: Felipe Balbi Signed-off-by: Nishanth Menon Reviewed-by: Grygorii Strashko Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-ds1307.c | 59 +++++++++++++--------------------------- 1 file changed, 19 insertions(+), 40 deletions(-) diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 6e76de1856fc..8ea496e54a2e 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -114,7 +114,6 @@ struct ds1307 { #define HAS_ALARM 1 /* bit 1 == irq claimed */ struct i2c_client *client; struct rtc_device *rtc; - struct work_struct work; s32 (*read_block_data)(const struct i2c_client *client, u8 command, u8 length, u8 *values); s32 (*write_block_data)(const struct i2c_client *client, u8 command, @@ -311,27 +310,17 @@ static s32 ds1307_native_smbus_read_block_data(const struct i2c_client *client, /*----------------------------------------------------------------------*/ /* - * The IRQ logic includes a "real" handler running in IRQ context just - * long enough to schedule this workqueue entry. We need a task context - * to talk to the RTC, since I2C I/O calls require that; and disable the - * IRQ until we clear its status on the chip, so that this handler can - * work with any type of triggering (not just falling edge). - * * The ds1337 and ds1339 both have two alarms, but we only use the first * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm * signal; ds1339 chips have only one alarm signal. */ -static void ds1307_work(struct work_struct *work) +static irqreturn_t ds1307_irq(int irq, void *dev_id) { - struct ds1307 *ds1307; - struct i2c_client *client; - struct mutex *lock; + struct i2c_client *client = dev_id; + struct ds1307 *ds1307 = i2c_get_clientdata(client); + struct mutex *lock = &ds1307->rtc->ops_lock; int stat, control; - ds1307 = container_of(work, struct ds1307, work); - client = ds1307->client; - lock = &ds1307->rtc->ops_lock; - mutex_lock(lock); stat = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS); if (stat < 0) @@ -352,18 +341,8 @@ static void ds1307_work(struct work_struct *work) } out: - if (test_bit(HAS_ALARM, &ds1307->flags)) - enable_irq(client->irq); mutex_unlock(lock); -} -static irqreturn_t ds1307_irq(int irq, void *dev_id) -{ - struct i2c_client *client = dev_id; - struct ds1307 *ds1307 = i2c_get_clientdata(client); - - disable_irq_nosync(irq); - schedule_work(&ds1307->work); return IRQ_HANDLED; } @@ -634,13 +613,14 @@ static const struct rtc_class_ops ds13xx_rtc_ops = { MCP794XX_BIT_ALMX_C1 | \ MCP794XX_BIT_ALMX_C2) -static void mcp794xx_work(struct work_struct *work) +static irqreturn_t mcp794xx_irq(int irq, void *dev_id) { - struct ds1307 *ds1307 = container_of(work, struct ds1307, work); - struct i2c_client *client = ds1307->client; + struct i2c_client *client = dev_id; + struct ds1307 *ds1307 = i2c_get_clientdata(client); + struct mutex *lock = &ds1307->rtc->ops_lock; int reg, ret; - mutex_lock(&ds1307->rtc->ops_lock); + mutex_lock(lock); /* Check and clear alarm 0 interrupt flag. */ reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_ALARM0_CTRL); @@ -665,9 +645,9 @@ static void mcp794xx_work(struct work_struct *work) rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); out: - if (test_bit(HAS_ALARM, &ds1307->flags)) - enable_irq(client->irq); - mutex_unlock(&ds1307->rtc->ops_lock); + mutex_unlock(lock); + + return IRQ_HANDLED; } static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) @@ -896,6 +876,8 @@ static int ds1307_probe(struct i2c_client *client, bool want_irq = false; unsigned char *buf; struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); + irq_handler_t irq_handler = ds1307_irq; + static const int bbsqi_bitpos[] = { [ds_1337] = 0, [ds_1339] = DS1339_BIT_BBSQI, @@ -962,8 +944,6 @@ static int ds1307_probe(struct i2c_client *client, * running on Vbackup (BBSQI/BBSQW) */ if (ds1307->client->irq > 0 && chip->alarm) { - INIT_WORK(&ds1307->work, ds1307_work); - ds1307->regs[0] |= DS1337_BIT_INTCN | bbsqi_bitpos[ds1307->type]; ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE); @@ -1053,7 +1033,7 @@ static int ds1307_probe(struct i2c_client *client, case mcp794xx: rtc_ops = &mcp794xx_rtc_ops; if (ds1307->client->irq > 0 && chip->alarm) { - INIT_WORK(&ds1307->work, mcp794xx_work); + irq_handler = mcp794xx_irq; want_irq = true; } break; @@ -1176,8 +1156,9 @@ read_rtc: } if (want_irq) { - err = request_irq(client->irq, ds1307_irq, IRQF_SHARED, - ds1307->rtc->name, client); + err = request_threaded_irq(client->irq, NULL, irq_handler, + IRQF_SHARED | IRQF_ONESHOT, + ds1307->rtc->name, client); if (err) { client->irq = 0; dev_err(&client->dev, "unable to request IRQ!\n"); @@ -1231,10 +1212,8 @@ static int ds1307_remove(struct i2c_client *client) { struct ds1307 *ds1307 = i2c_get_clientdata(client); - if (test_and_clear_bit(HAS_ALARM, &ds1307->flags)) { + if (test_and_clear_bit(HAS_ALARM, &ds1307->flags)) free_irq(client->irq, client); - cancel_work_sync(&ds1307->work); - } if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags)) sysfs_remove_bin_file(&client->dev.kobj, ds1307->nvram);