diff options
author | Daniel Willerud <daniel.willerud@stericsson.com> | 2011-03-05 13:46:13 +0300 |
---|---|---|
committer | Samuel Ortiz <sameo@linux.intel.com> | 2011-03-23 12:42:04 +0300 |
commit | 6321992cd3c56bab6cc52e3384951e12616805a1 (patch) | |
tree | 9a5d028aeb44c0f061c1e5a49735b82a7c609f56 /drivers/mfd | |
parent | cf16943947cef089c564d2be0ae9d96a285f495e (diff) | |
download | linux-6321992cd3c56bab6cc52e3384951e12616805a1.tar.xz |
mfd: Reentrance and revamp ab8500 gpadc fetching interface
This revamps the interface so that AB8500 GPADCs are fetched by
name. Probed GPADCs are added to a list and this list is searched
for a matching GPADC. This makes it possible to have multiple
AB8500 GPADC instances instead of it being a singleton, and
rids the need to keep a GPADC pointer around in the core AB8500
MFD struct.
Currently the match is made to the device name which is by default
numbered from the device instance such as "ab8500-gpadc.0" but
by using the .init_name field of the device a more intiutive
naming for the GPADC blocks can be achieved if desired.
Signed-off-by: Daniel Willerud <daniel.willerud@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/mfd')
-rw-r--r-- | drivers/mfd/ab8500-gpadc.c | 115 |
1 files changed, 70 insertions, 45 deletions
diff --git a/drivers/mfd/ab8500-gpadc.c b/drivers/mfd/ab8500-gpadc.c index f60f71f4b473..178cbc55caea 100644 --- a/drivers/mfd/ab8500-gpadc.c +++ b/drivers/mfd/ab8500-gpadc.c @@ -3,6 +3,7 @@ * * License Terms: GNU General Public License v2 * Author: Arun R Murthy <arun.murthy@stericsson.com> + * Author: Daniel Willerud <daniel.willerud@stericsson.com> */ #include <linux/init.h> #include <linux/module.h> @@ -15,6 +16,7 @@ #include <linux/regulator/consumer.h> #include <linux/err.h> #include <linux/slab.h> +#include <linux/list.h> #include <linux/mfd/ab8500.h> #include <linux/mfd/abx500.h> #include <linux/mfd/ab8500/ab8500-gpadc.h> @@ -48,21 +50,41 @@ /** * struct ab8500_gpadc - ab8500 GPADC device information * @dev: pointer to the struct device - * @parent: pointer to the parent device structure ab8500 + * @node: a list of AB8500 GPADCs, hence prepared for + reentrance * @ab8500_gpadc_complete: pointer to the struct completion, to indicate * the completion of gpadc conversion * @ab8500_gpadc_lock: structure of type mutex * @regu: pointer to the struct regulator * @irq: interrupt number that is used by gpadc */ -static struct ab8500_gpadc { +struct ab8500_gpadc { struct device *dev; - struct ab8500 *parent; + struct list_head node; struct completion ab8500_gpadc_complete; struct mutex ab8500_gpadc_lock; struct regulator *regu; int irq; -} *di; +}; + +static LIST_HEAD(ab8500_gpadc_list); + +/** + * ab8500_gpadc_get() - returns a reference to the primary AB8500 GPADC + * (i.e. the first GPADC in the instance list) + */ +struct ab8500_gpadc *ab8500_gpadc_get(char *name) +{ + struct ab8500_gpadc *gpadc; + + list_for_each_entry(gpadc, &ab8500_gpadc_list, node) { + if (!strcmp(name, dev_name(gpadc->dev))) + return gpadc; + } + + return ERR_PTR(-ENOENT); +} +EXPORT_SYMBOL(ab8500_gpadc_get); /** * ab8500_gpadc_convert() - gpadc conversion @@ -72,24 +94,24 @@ static struct ab8500_gpadc { * data. Thereafter calibration has to be made to obtain the * data in the required quantity measurement. */ -int ab8500_gpadc_convert(u8 input) +int ab8500_gpadc_convert(struct ab8500_gpadc *gpadc, u8 input) { int ret; u16 data = 0; int looplimit = 0; u8 val, low_data, high_data; - if (!di) + if (!gpadc) return -ENODEV; - mutex_lock(&di->ab8500_gpadc_lock); + mutex_lock(&gpadc->ab8500_gpadc_lock); /* Enable VTVout LDO this is required for GPADC */ - regulator_enable(di->regu); + regulator_enable(gpadc->regu); /* Check if ADC is not busy, lock and proceed */ do { - ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC, - AB8500_GPADC_STAT_REG, &val); + ret = abx500_get_register_interruptible(gpadc->dev, + AB8500_GPADC, AB8500_GPADC_STAT_REG, &val); if (ret < 0) goto out; if (!(val & GPADC_BUSY)) @@ -97,75 +119,76 @@ int ab8500_gpadc_convert(u8 input) msleep(10); } while (++looplimit < 10); if (looplimit >= 10 && (val & GPADC_BUSY)) { - dev_err(di->dev, "gpadc_conversion: GPADC busy"); + dev_err(gpadc->dev, "gpadc_conversion: GPADC busy"); ret = -EINVAL; goto out; } /* Enable GPADC */ - ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC, - AB8500_GPADC_CTRL1_REG, EN_GPADC, EN_GPADC); + ret = abx500_mask_and_set_register_interruptible(gpadc->dev, + AB8500_GPADC, AB8500_GPADC_CTRL1_REG, EN_GPADC, EN_GPADC); if (ret < 0) { - dev_err(di->dev, "gpadc_conversion: enable gpadc failed\n"); + dev_err(gpadc->dev, "gpadc_conversion: enable gpadc failed\n"); goto out; } /* Select the input source and set average samples to 16 */ - ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC, + ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_CTRL2_REG, (input | SW_AVG_16)); if (ret < 0) { - dev_err(di->dev, + dev_err(gpadc->dev, "gpadc_conversion: set avg samples failed\n"); goto out; } /* Enable ADC, Buffering and select rising edge, start Conversion */ - ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC, - AB8500_GPADC_CTRL1_REG, EN_BUF, EN_BUF); + ret = abx500_mask_and_set_register_interruptible(gpadc->dev, + AB8500_GPADC, AB8500_GPADC_CTRL1_REG, EN_BUF, EN_BUF); if (ret < 0) { - dev_err(di->dev, + dev_err(gpadc->dev, "gpadc_conversion: select falling edge failed\n"); goto out; } - ret = abx500_mask_and_set_register_interruptible(di->dev, AB8500_GPADC, - AB8500_GPADC_CTRL1_REG, ADC_SW_CONV, ADC_SW_CONV); + ret = abx500_mask_and_set_register_interruptible(gpadc->dev, + AB8500_GPADC, AB8500_GPADC_CTRL1_REG, ADC_SW_CONV, ADC_SW_CONV); if (ret < 0) { - dev_err(di->dev, + dev_err(gpadc->dev, "gpadc_conversion: start s/w conversion failed\n"); goto out; } /* wait for completion of conversion */ - if (!wait_for_completion_timeout(&di->ab8500_gpadc_complete, 2*HZ)) { - dev_err(di->dev, + if (!wait_for_completion_timeout(&gpadc->ab8500_gpadc_complete, 2*HZ)) { + dev_err(gpadc->dev, "timeout: didnt recieve GPADC conversion interrupt\n"); ret = -EINVAL; goto out; } /* Read the converted RAW data */ - ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC, + ret = abx500_get_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_MANDATAL_REG, &low_data); if (ret < 0) { - dev_err(di->dev, "gpadc_conversion: read low data failed\n"); + dev_err(gpadc->dev, "gpadc_conversion: read low data failed\n"); goto out; } - ret = abx500_get_register_interruptible(di->dev, AB8500_GPADC, + ret = abx500_get_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_MANDATAH_REG, &high_data); if (ret < 0) { - dev_err(di->dev, "gpadc_conversion: read high data failed\n"); + dev_err(gpadc->dev, + "gpadc_conversion: read high data failed\n"); goto out; } data = (high_data << 8) | low_data; /* Disable GPADC */ - ret = abx500_set_register_interruptible(di->dev, AB8500_GPADC, + ret = abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_CTRL1_REG, DIS_GPADC); if (ret < 0) { - dev_err(di->dev, "gpadc_conversion: disable gpadc failed\n"); + dev_err(gpadc->dev, "gpadc_conversion: disable gpadc failed\n"); goto out; } /* Disable VTVout LDO this is required for GPADC */ - regulator_disable(di->regu); - mutex_unlock(&di->ab8500_gpadc_lock); + regulator_disable(gpadc->regu); + mutex_unlock(&gpadc->ab8500_gpadc_lock); return data; out: @@ -175,12 +198,12 @@ out: * GPADC status register to go low. In V1.1 there wait_for_completion * seems to timeout when waiting for an interrupt.. Not seen in V2.0 */ - (void) abx500_set_register_interruptible(di->dev, AB8500_GPADC, + (void) abx500_set_register_interruptible(gpadc->dev, AB8500_GPADC, AB8500_GPADC_CTRL1_REG, DIS_GPADC); - regulator_disable(di->regu); - mutex_unlock(&di->ab8500_gpadc_lock); - dev_err(di->dev, "gpadc_conversion: Failed to AD convert channel %d\n", - input); + regulator_disable(gpadc->regu); + mutex_unlock(&gpadc->ab8500_gpadc_lock); + dev_err(gpadc->dev, + "gpadc_conversion: Failed to AD convert channel %d\n", input); return ret; } EXPORT_SYMBOL(ab8500_gpadc_convert); @@ -195,9 +218,9 @@ EXPORT_SYMBOL(ab8500_gpadc_convert); * can be read from the registers. * Returns IRQ status(IRQ_HANDLED) */ -static irqreturn_t ab8500_bm_gpswadcconvend_handler(int irq, void *_di) +static irqreturn_t ab8500_bm_gpswadcconvend_handler(int irq, void *_gpadc) { - struct ab8500_gpadc *gpadc = _di; + struct ab8500_gpadc *gpadc = _gpadc; complete(&gpadc->ab8500_gpadc_complete); @@ -215,16 +238,16 @@ static int __devinit ab8500_gpadc_probe(struct platform_device *pdev) return -ENOMEM; } - gpadc->parent = dev_get_drvdata(pdev->dev.parent); gpadc->irq = platform_get_irq_byname(pdev, "SW_CONV_END"); if (gpadc->irq < 0) { - dev_err(gpadc->dev, "failed to get platform irq-%d\n", di->irq); + dev_err(gpadc->dev, "failed to get platform irq-%d\n", + gpadc->irq); ret = gpadc->irq; goto fail; } gpadc->dev = &pdev->dev; - mutex_init(&di->ab8500_gpadc_lock); + mutex_init(&gpadc->ab8500_gpadc_lock); /* Initialize completion used to notify completion of conversion */ init_completion(&gpadc->ab8500_gpadc_complete); @@ -246,7 +269,7 @@ static int __devinit ab8500_gpadc_probe(struct platform_device *pdev) dev_err(gpadc->dev, "failed to get vtvout LDO\n"); goto fail; } - di = gpadc; + list_add_tail(&gpadc->node, &ab8500_gpadc_list); dev_dbg(gpadc->dev, "probe success\n"); return 0; fail: @@ -259,8 +282,10 @@ static int __devexit ab8500_gpadc_remove(struct platform_device *pdev) { struct ab8500_gpadc *gpadc = platform_get_drvdata(pdev); + /* remove this gpadc entry from the list */ + list_del(&gpadc->node); /* remove interrupt - completion of Sw ADC conversion */ - free_irq(gpadc->irq, di); + free_irq(gpadc->irq, gpadc); /* disable VTVout LDO that is being used by GPADC */ regulator_put(gpadc->regu); kfree(gpadc); @@ -291,6 +316,6 @@ subsys_initcall_sync(ab8500_gpadc_init); module_exit(ab8500_gpadc_exit); MODULE_LICENSE("GPL v2"); -MODULE_AUTHOR("Arun R Murthy"); +MODULE_AUTHOR("Arun R Murthy, Daniel Willerud"); MODULE_ALIAS("platform:ab8500_gpadc"); MODULE_DESCRIPTION("AB8500 GPADC driver"); |