diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-s3c2410.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 244 |
1 files changed, 100 insertions, 144 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 362a6de54833..38dc1cacfd8b 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -163,15 +163,14 @@ static const struct of_device_id s3c24xx_i2c_match[] = { MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match); #endif -/* s3c24xx_get_device_quirks - * +/* * Get controller type either from device tree or platform device variant. -*/ - + */ static inline kernel_ulong_t s3c24xx_get_device_quirks(struct platform_device *pdev) { if (pdev->dev.of_node) { const struct of_device_id *match; + match = of_match_node(s3c24xx_i2c_match, pdev->dev.of_node); return (kernel_ulong_t)match->data; } @@ -179,12 +178,10 @@ static inline kernel_ulong_t s3c24xx_get_device_quirks(struct platform_device *p return platform_get_device_id(pdev)->driver_data; } -/* s3c24xx_i2c_master_complete - * - * complete the message and wake up the caller, using the given return code, +/* + * Complete the message and wake up the caller, using the given return code, * or zero to mean ok. -*/ - + */ static inline void s3c24xx_i2c_master_complete(struct s3c24xx_i2c *i2c, int ret) { dev_dbg(i2c->dev, "master_complete %d\n", ret); @@ -217,7 +214,6 @@ static inline void s3c24xx_i2c_enable_ack(struct s3c24xx_i2c *i2c) } /* irq enable/disable functions */ - static inline void s3c24xx_i2c_disable_irq(struct s3c24xx_i2c *i2c) { unsigned long tmp; @@ -251,11 +247,9 @@ static bool is_ack(struct s3c24xx_i2c *i2c) return false; } -/* s3c24xx_i2c_message_start - * +/* * put the start of a message onto the bus -*/ - + */ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c, struct i2c_msg *msg) { @@ -284,9 +278,10 @@ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c, dev_dbg(i2c->dev, "START: %08lx to IICSTAT, %02x to DS\n", stat, addr); writeb(addr, i2c->regs + S3C2410_IICDS); - /* delay here to ensure the data byte has gotten onto the bus - * before the transaction is started */ - + /* + * delay here to ensure the data byte has gotten onto the bus + * before the transaction is started + */ ndelay(i2c->tx_setup); dev_dbg(i2c->dev, "iiccon, %08lx\n", iiccon); @@ -361,50 +356,46 @@ static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret) s3c24xx_i2c_disable_irq(i2c); } -/* helper functions to determine the current state in the set of - * messages we are sending */ +/* + * helper functions to determine the current state in the set of + * messages we are sending + */ -/* is_lastmsg() - * +/* * returns TRUE if the current message is the last in the set -*/ - + */ static inline int is_lastmsg(struct s3c24xx_i2c *i2c) { return i2c->msg_idx >= (i2c->msg_num - 1); } -/* is_msglast - * +/* * returns TRUE if we this is the last byte in the current message -*/ - + */ static inline int is_msglast(struct s3c24xx_i2c *i2c) { - /* msg->len is always 1 for the first byte of smbus block read. + /* + * msg->len is always 1 for the first byte of smbus block read. * Actual length will be read from slave. More bytes will be - * read according to the length then. */ + * read according to the length then. + */ if (i2c->msg->flags & I2C_M_RECV_LEN && i2c->msg->len == 1) return 0; return i2c->msg_ptr == i2c->msg->len-1; } -/* is_msgend - * +/* * returns TRUE if we reached the end of the current message -*/ - + */ static inline int is_msgend(struct s3c24xx_i2c *i2c) { return i2c->msg_ptr >= i2c->msg->len; } -/* i2c_s3c_irq_nextbyte - * +/* * process an interrupt and work out what to do */ - static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) { unsigned long tmp; @@ -423,14 +414,13 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) goto out_ack; case STATE_START: - /* last thing we did was send a start condition on the + /* + * last thing we did was send a start condition on the * bus, or started a new i2c message */ - if (iicstat & S3C2410_IICSTAT_LASTBIT && !(i2c->msg->flags & I2C_M_IGNORE_NAK)) { /* ack was not received... */ - dev_dbg(i2c->dev, "ack was not received\n"); s3c24xx_i2c_stop(i2c, -ENXIO); goto out_ack; @@ -441,9 +431,10 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) else i2c->state = STATE_WRITE; - /* terminate the transfer if there is nothing to do - * as this is used by the i2c probe to find devices. */ - + /* + * Terminate the transfer if there is nothing to do + * as this is used by the i2c probe to find devices. + */ if (is_lastmsg(i2c) && i2c->msg->len == 0) { s3c24xx_i2c_stop(i2c, 0); goto out_ack; @@ -452,14 +443,16 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) if (i2c->state == STATE_READ) goto prepare_read; - /* fall through to the write state, as we will need to - * send a byte as well */ + /* + * fall through to the write state, as we will need to + * send a byte as well + */ case STATE_WRITE: - /* we are writing data to the device... check for the + /* + * we are writing data to the device... check for the * end of the message, and if so, work out what to do */ - if (!(i2c->msg->flags & I2C_M_IGNORE_NAK)) { if (iicstat & S3C2410_IICSTAT_LASTBIT) { dev_dbg(i2c->dev, "WRITE: No Ack\n"); @@ -475,12 +468,13 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) byte = i2c->msg->buf[i2c->msg_ptr++]; writeb(byte, i2c->regs + S3C2410_IICDS); - /* delay after writing the byte to allow the + /* + * delay after writing the byte to allow the * data setup time on the bus, as writing the * data to the register causes the first bit * to appear on SDA, and SCL will change as - * soon as the interrupt is acknowledged */ - + * soon as the interrupt is acknowledged + */ ndelay(i2c->tx_setup); } else if (!is_lastmsg(i2c)) { @@ -496,10 +490,11 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) if (i2c->msg->flags & I2C_M_NOSTART) { if (i2c->msg->flags & I2C_M_RD) { - /* cannot do this, the controller + /* + * cannot do this, the controller * forces us to send a new START - * when we change direction */ - + * when we change direction + */ s3c24xx_i2c_stop(i2c, -EINVAL); } @@ -512,17 +507,16 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) } else { /* send stop */ - s3c24xx_i2c_stop(i2c, 0); } break; case STATE_READ: - /* we have a byte of data in the data register, do + /* + * we have a byte of data in the data register, do * something with it, and then work out whether we are * going to do any more read/write */ - byte = readb(i2c->regs + S3C2410_IICDS); i2c->msg->buf[i2c->msg_ptr++] = byte; @@ -537,9 +531,10 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) s3c24xx_i2c_disable_ack(i2c); } else if (is_msgend(i2c)) { - /* ok, we've read the entire buffer, see if there - * is anything else we need to do */ - + /* + * ok, we've read the entire buffer, see if there + * is anything else we need to do + */ if (is_lastmsg(i2c)) { /* last message, send stop and complete */ dev_dbg(i2c->dev, "READ: Send Stop\n"); @@ -568,11 +563,9 @@ static int i2c_s3c_irq_nextbyte(struct s3c24xx_i2c *i2c, unsigned long iicstat) return ret; } -/* s3c24xx_i2c_irq - * +/* * top level IRQ servicing routine -*/ - + */ static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id) { struct s3c24xx_i2c *i2c = dev_id; @@ -595,9 +588,10 @@ static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id) goto out; } - /* pretty much this leaves us with the fact that we've - * transmitted or received whatever byte we last sent */ - + /* + * pretty much this leaves us with the fact that we've + * transmitted or received whatever byte we last sent + */ i2c_s3c_irq_nextbyte(i2c, status); out: @@ -630,11 +624,9 @@ static inline void s3c24xx_i2c_disable_bus(struct s3c24xx_i2c *i2c) } -/* s3c24xx_i2c_set_master - * +/* * get the i2c bus for a master transaction -*/ - + */ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) { unsigned long iicstat; @@ -652,11 +644,9 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) return -ETIMEDOUT; } -/* s3c24xx_i2c_wait_idle - * +/* * wait for the i2c bus to become idle. -*/ - + */ static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) { unsigned long iicstat; @@ -706,11 +696,9 @@ static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) dev_warn(i2c->dev, "timeout waiting for bus idle\n"); } -/* s3c24xx_i2c_doxfer - * +/* * this starts an i2c transfer -*/ - + */ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int num) { @@ -749,9 +737,10 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, ret = i2c->msg_idx; - /* having these next two as dev_err() makes life very - * noisy when doing an i2cdetect */ - + /* + * Having these next two as dev_err() makes life very + * noisy when doing an i2cdetect + */ if (timeout == 0) dev_dbg(i2c->dev, "timeout\n"); else if (ret != num) @@ -771,12 +760,10 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, return ret; } -/* s3c24xx_i2c_xfer - * +/* * first port of call from the i2c bus code when an message needs * transferring across the i2c bus. -*/ - + */ static int s3c24xx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { @@ -814,17 +801,14 @@ static u32 s3c24xx_i2c_func(struct i2c_adapter *adap) } /* i2c bus registration info */ - static const struct i2c_algorithm s3c24xx_i2c_algorithm = { .master_xfer = s3c24xx_i2c_xfer, .functionality = s3c24xx_i2c_func, }; -/* s3c24xx_i2c_calcdivisor - * +/* * return the divisor settings for a given frequency -*/ - + */ static int s3c24xx_i2c_calcdivisor(unsigned long clkin, unsigned int wanted, unsigned int *div1, unsigned int *divs) { @@ -850,13 +834,11 @@ static int s3c24xx_i2c_calcdivisor(unsigned long clkin, unsigned int wanted, return clkin / (calc_divs * calc_div1); } -/* s3c24xx_i2c_clockrate - * +/* * work out a divisor for the user requested frequency setting, * either by the requested frequency, or scanning the acceptable * range of frequencies until something is found -*/ - + */ static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got) { struct s3c2410_platform_i2c *pdata = i2c->pdata; @@ -944,7 +926,7 @@ static int s3c24xx_i2c_cpufreq_transition(struct notifier_block *nb, i2c_unlock_adapter(&i2c->adap); if (ret < 0) - dev_err(i2c->dev, "cannot find frequency\n"); + dev_err(i2c->dev, "cannot find frequency (%d)\n", ret); else dev_info(i2c->dev, "setting freq %d\n", got); } @@ -995,7 +977,8 @@ static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c) ret = gpio_request(gpio, "i2c-bus"); if (ret) { - dev_err(i2c->dev, "gpio [%d] request failed\n", gpio); + dev_err(i2c->dev, "gpio [%d] request failed (%d)\n", + gpio, ret); goto free_gpio; } } @@ -1028,11 +1011,9 @@ static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c) } #endif -/* s3c24xx_i2c_init - * +/* * initialise the controller, set the IO lines and frequency -*/ - + */ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c) { struct s3c2410_platform_i2c *pdata; @@ -1068,11 +1049,9 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c) } #ifdef CONFIG_OF -/* s3c24xx_i2c_parse_dt - * +/* * Parse the device tree node and retreive the platform data. -*/ - + */ static void s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) { @@ -1105,17 +1084,9 @@ s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) } #else static void -s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) -{ - return; -} +s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) { } #endif -/* s3c24xx_i2c_probe - * - * called by the bus driver when a suitable device is found -*/ - static int s3c24xx_i2c_probe(struct platform_device *pdev) { struct s3c24xx_i2c *i2c; @@ -1156,7 +1127,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) init_waitqueue_head(&i2c->wait); /* find the clock and enable it */ - i2c->dev = &pdev->dev; i2c->clk = devm_clk_get(&pdev->dev, "i2c"); if (IS_ERR(i2c->clk)) { @@ -1166,9 +1136,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk); - /* map the registers */ - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); i2c->regs = devm_ioremap_resource(&pdev->dev, res); @@ -1179,33 +1147,35 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) i2c->regs, res); /* setup info block for the i2c core */ - i2c->adap.algo_data = i2c; i2c->adap.dev.parent = &pdev->dev; - i2c->pctrl = devm_pinctrl_get_select_default(i2c->dev); /* inititalise the i2c gpio lines */ - - if (i2c->pdata->cfg_gpio) { + if (i2c->pdata->cfg_gpio) i2c->pdata->cfg_gpio(to_platform_device(i2c->dev)); - } else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) { + else if (IS_ERR(i2c->pctrl) && s3c24xx_i2c_parse_dt_gpio(i2c)) return -EINVAL; - } /* initialise the i2c controller */ + ret = clk_prepare_enable(i2c->clk); + if (ret) { + dev_err(&pdev->dev, "I2C clock enable failed\n"); + return ret; + } - clk_prepare_enable(i2c->clk); ret = s3c24xx_i2c_init(i2c); clk_disable(i2c->clk); if (ret != 0) { dev_err(&pdev->dev, "I2C controller init failed\n"); + clk_unprepare(i2c->clk); return ret; } - /* find the IRQ for this unit (note, this relies on the init call to + + /* + * find the IRQ for this unit (note, this relies on the init call to * ensure no current IRQs pending */ - if (!(i2c->quirks & QUIRK_POLL)) { i2c->irq = ret = platform_get_irq(pdev, 0); if (ret <= 0) { @@ -1214,9 +1184,8 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) return ret; } - ret = devm_request_irq(&pdev->dev, i2c->irq, s3c24xx_i2c_irq, 0, - dev_name(&pdev->dev), i2c); - + ret = devm_request_irq(&pdev->dev, i2c->irq, s3c24xx_i2c_irq, + 0, dev_name(&pdev->dev), i2c); if (ret != 0) { dev_err(&pdev->dev, "cannot claim IRQ %d\n", i2c->irq); clk_unprepare(i2c->clk); @@ -1231,12 +1200,12 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) return ret; } - /* Note, previous versions of the driver used i2c_add_adapter() + /* + * Note, previous versions of the driver used i2c_add_adapter() * to add the bus at any number. We now pass the bus number via * the platform data, so if unset it will now default to always * being bus 0. */ - i2c->adap.nr = i2c->pdata->bus_num; i2c->adap.dev.of_node = pdev->dev.of_node; @@ -1257,11 +1226,6 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) return 0; } -/* s3c24xx_i2c_remove - * - * called when device is removed from the bus -*/ - static int s3c24xx_i2c_remove(struct platform_device *pdev) { struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); @@ -1316,14 +1280,8 @@ static int s3c24xx_i2c_resume_noirq(struct device *dev) #ifdef CONFIG_PM static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = { -#ifdef CONFIG_PM_SLEEP - .suspend_noirq = s3c24xx_i2c_suspend_noirq, - .resume_noirq = s3c24xx_i2c_resume_noirq, - .freeze_noirq = s3c24xx_i2c_suspend_noirq, - .thaw_noirq = s3c24xx_i2c_resume_noirq, - .poweroff_noirq = s3c24xx_i2c_suspend_noirq, - .restore_noirq = s3c24xx_i2c_resume_noirq, -#endif + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(s3c24xx_i2c_suspend_noirq, + s3c24xx_i2c_resume_noirq) }; #define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops) @@ -1331,8 +1289,6 @@ static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = { #define S3C24XX_DEV_PM_OPS NULL #endif -/* device driver for platform bus bits */ - static struct platform_driver s3c24xx_i2c_driver = { .probe = s3c24xx_i2c_probe, .remove = s3c24xx_i2c_remove, |