[PATCH v4 1/4] mfd: mc13xxx-core: Prepare for separate spi and i2c backends.

From: Marc Reilly
Date: Mon Mar 19 2012 - 01:00:41 EST

This patch abstracts the bus specific operations from the driver core.
Generic init and cleanup is consolidated into mc13xxx_common_*.
spi specific functions are renamed to reflect such.
(The irq member of the mc13xxx struct is no longer redundant, it's used
to store the irq for cleanup time).

Signed-off-by: Marc Reilly <marc@xxxxxxxxxxxxxxx>
---
drivers/mfd/mc13xxx-core.c | 187 ++++++++++++++++++++++++++------------------
1 files changed, 112 insertions(+), 75 deletions(-)

diff --git a/drivers/mfd/mc13xxx-core.c b/drivers/mfd/mc13xxx-core.c
index 7122386..0753402 100644
--- a/drivers/mfd/mc13xxx-core.c
+++ b/drivers/mfd/mc13xxx-core.c
@@ -22,8 +22,18 @@
#include <linux/of_device.h>
#include <linux/of_gpio.h>

+enum mc13xxx_id {
+ MC13XXX_ID_MC13783,
+ MC13XXX_ID_MC13892,
+ MC13XXX_ID_INVALID,
+};
+
struct mc13xxx {
struct spi_device *spidev;
+
+ struct device *dev;
+ enum mc13xxx_id ictype;
+
struct mutex lock;
int irq;
int flags;
@@ -144,36 +154,32 @@ struct mc13xxx {
void mc13xxx_lock(struct mc13xxx *mc13xxx)
{
if (!mutex_trylock(&mc13xxx->lock)) {
- dev_dbg(&mc13xxx->spidev->dev, "wait for %s from %pf\n",
+ dev_dbg(mc13xxx->dev, "wait for %s from %pf\n",
__func__, __builtin_return_address(0));

mutex_lock(&mc13xxx->lock);
}
- dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
+ dev_dbg(mc13xxx->dev, "%s from %pf\n",
__func__, __builtin_return_address(0));
}
EXPORT_SYMBOL(mc13xxx_lock);

void mc13xxx_unlock(struct mc13xxx *mc13xxx)
{
- dev_dbg(&mc13xxx->spidev->dev, "%s from %pf\n",
+ dev_dbg(mc13xxx->dev, "%s from %pf\n",
__func__, __builtin_return_address(0));
mutex_unlock(&mc13xxx->lock);
}
EXPORT_SYMBOL(mc13xxx_unlock);

#define MC13XXX_REGOFFSET_SHIFT 25
-int mc13xxx_reg_read(struct mc13xxx *mc13xxx, unsigned int offset, u32 *val)
+static int mc13xxx_spi_reg_read(struct mc13xxx *mc13xxx,
+ unsigned int offset, u32 *val)
{
struct spi_transfer t;
struct spi_message m;
int ret;

- BUG_ON(!mutex_is_locked(&mc13xxx->lock));
-
- if (offset > MC13XXX_NUMREGS)
- return -EINVAL;
-
*val = offset << MC13XXX_REGOFFSET_SHIFT;

memset(&t, 0, sizeof(t));
@@ -195,26 +201,17 @@ int mc13xxx_reg_read(struct mc13xxx *mc13xxx, unsigned int offset, u32 *val)

*val &= 0xffffff;

- dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
-
return 0;
}
-EXPORT_SYMBOL(mc13xxx_reg_read);

-int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val)
+static int mc13xxx_spi_reg_write(struct mc13xxx *mc13xxx, unsigned int offset,
+ u32 val)
{
u32 buf;
struct spi_transfer t;
struct spi_message m;
int ret;

- BUG_ON(!mutex_is_locked(&mc13xxx->lock));
-
- dev_vdbg(&mc13xxx->spidev->dev, "[0x%02x] <- 0x%06x\n", offset, val);
-
- if (offset > MC13XXX_NUMREGS || val > 0xffffff)
- return -EINVAL;
-
buf = 1 << 31 | offset << MC13XXX_REGOFFSET_SHIFT | val;

memset(&t, 0, sizeof(t));
@@ -235,6 +232,34 @@ int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val)

return 0;
}
+
+int mc13xxx_reg_read(struct mc13xxx *mc13xxx, unsigned int offset, u32 *val)
+{
+ int ret;
+
+ BUG_ON(!mutex_is_locked(&mc13xxx->lock));
+
+ if (offset > MC13XXX_NUMREGS)
+ return -EINVAL;
+
+ ret = mc13xxx_spi_reg_read(mc13xxx, offset, val);
+ dev_vdbg(mc13xxx->dev, "[0x%02x] -> 0x%06x\n", offset, *val);
+
+ return ret;
+}
+EXPORT_SYMBOL(mc13xxx_reg_read);
+
+int mc13xxx_reg_write(struct mc13xxx *mc13xxx, unsigned int offset, u32 val)
+{
+ BUG_ON(!mutex_is_locked(&mc13xxx->lock));
+
+ dev_vdbg(mc13xxx->dev, "[0x%02x] <- 0x%06x\n", offset, val);
+
+ if (offset > MC13XXX_NUMREGS || val > 0xffffff)
+ return -EINVAL;
+
+ return mc13xxx_spi_reg_write(mc13xxx, offset, val);
+}
EXPORT_SYMBOL(mc13xxx_reg_write);

int mc13xxx_reg_rmw(struct mc13xxx *mc13xxx, unsigned int offset,
@@ -439,7 +464,7 @@ static int mc13xxx_irq_handle(struct mc13xxx *mc13xxx,
if (handled == IRQ_HANDLED)
num_handled++;
} else {
- dev_err(&mc13xxx->spidev->dev,
+ dev_err(mc13xxx->dev,
"BUG: irq %u but no handler\n",
baseirq + irq);

@@ -475,25 +500,23 @@ static irqreturn_t mc13xxx_irq_thread(int irq, void *data)
return IRQ_RETVAL(handled);
}

-enum mc13xxx_id {
- MC13XXX_ID_MC13783,
- MC13XXX_ID_MC13892,
- MC13XXX_ID_INVALID,
-};
-
static const char *mc13xxx_chipname[] = {
[MC13XXX_ID_MC13783] = "mc13783",
[MC13XXX_ID_MC13892] = "mc13892",
};

#define maskval(reg, mask) (((reg) & (mask)) >> __ffs(mask))
-static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
+static int mc13xxx_identify(struct mc13xxx *mc13xxx)
{
u32 icid;
u32 revision;
- const char *name;
int ret;

+ /*
+ * Get the generation ID from register 46, as apparently some older
+ * IC revisions only have this info at this location. Newer ICs seem to
+ * have both.
+ */
ret = mc13xxx_reg_read(mc13xxx, 46, &icid);
if (ret)
return ret;
@@ -502,26 +525,23 @@ static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)

switch (icid) {
case 2:
- *id = MC13XXX_ID_MC13783;
- name = "mc13783";
+ mc13xxx->ictype = MC13XXX_ID_MC13783;
break;
case 7:
- *id = MC13XXX_ID_MC13892;
- name = "mc13892";
+ mc13xxx->ictype = MC13XXX_ID_MC13892;
break;
default:
- *id = MC13XXX_ID_INVALID;
+ mc13xxx->ictype = MC13XXX_ID_INVALID;
break;
}

- if (*id == MC13XXX_ID_MC13783 || *id == MC13XXX_ID_MC13892) {
+ if (mc13xxx->ictype == MC13XXX_ID_MC13783 ||
+ mc13xxx->ictype == MC13XXX_ID_MC13892) {
ret = mc13xxx_reg_read(mc13xxx, MC13XXX_REVISION, &revision);
- if (ret)
- return ret;

- dev_info(&mc13xxx->spidev->dev, "%s: rev: %d.%d, "
+ dev_info(mc13xxx->dev, "%s: rev: %d.%d, "
"fin: %d, fab: %d, icid: %d/%d\n",
- mc13xxx_chipname[*id],
+ mc13xxx_chipname[mc13xxx->ictype],
maskval(revision, MC13XXX_REVISION_REVFULL),
maskval(revision, MC13XXX_REVISION_REVMETAL),
maskval(revision, MC13XXX_REVISION_FIN),
@@ -530,26 +550,12 @@ static int mc13xxx_identify(struct mc13xxx *mc13xxx, enum mc13xxx_id *id)
maskval(revision, MC13XXX_REVISION_ICIDCODE));
}

- if (*id != MC13XXX_ID_INVALID) {
- const struct spi_device_id *devid =
- spi_get_device_id(mc13xxx->spidev);
- if (!devid || devid->driver_data != *id)
- dev_warn(&mc13xxx->spidev->dev, "device id doesn't "
- "match auto detection!\n");
- }
-
- return 0;
+ return (mc13xxx->ictype == MC13XXX_ID_INVALID) ? -ENODEV : 0;
}

static const char *mc13xxx_get_chipname(struct mc13xxx *mc13xxx)
{
- const struct spi_device_id *devid =
- spi_get_device_id(mc13xxx->spidev);
-
- if (!devid)
- return NULL;
-
- return mc13xxx_chipname[devid->driver_data];
+ return mc13xxx_chipname[mc13xxx->ictype];
}

int mc13xxx_get_flags(struct mc13xxx *mc13xxx)
@@ -589,7 +595,7 @@ int mc13xxx_adc_do_conversion(struct mc13xxx *mc13xxx, unsigned int mode,
};
init_completion(&adcdone_data.done);

- dev_dbg(&mc13xxx->spidev->dev, "%s\n", __func__);
+ dev_dbg(mc13xxx->dev, "%s\n", __func__);

mc13xxx_lock(mc13xxx);

@@ -631,7 +637,7 @@ int mc13xxx_adc_do_conversion(struct mc13xxx *mc13xxx, unsigned int mode,
return -EINVAL;
}

- dev_dbg(&mc13xxx->spidev->dev, "%s: request irq\n", __func__);
+ dev_dbg(mc13xxx->dev, "%s: request irq\n", __func__);
mc13xxx_irq_request(mc13xxx, MC13XXX_IRQ_ADCDONE,
mc13xxx_handler_adcdone, __func__, &adcdone_data);
mc13xxx_irq_ack(mc13xxx, MC13XXX_IRQ_ADCDONE);
@@ -689,7 +695,7 @@ static int mc13xxx_add_subdevice_pdata(struct mc13xxx *mc13xxx,
if (!cell.name)
return -ENOMEM;

- return mfd_add_devices(&mc13xxx->spidev->dev, -1, &cell, 1, NULL, 0);
+ return mfd_add_devices(mc13xxx->dev, -1, &cell, 1, NULL, 0);
}

static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
@@ -700,7 +706,7 @@ static int mc13xxx_add_subdevice(struct mc13xxx *mc13xxx, const char *format)
#ifdef CONFIG_OF
static int mc13xxx_probe_flags_dt(struct mc13xxx *mc13xxx)
{
- struct device_node *np = mc13xxx->spidev->dev.of_node;
+ struct device_node *np = mc13xxx->dev.of_node;

if (!np)
return -ENODEV;
@@ -746,13 +752,17 @@ static const struct of_device_id mc13xxx_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);

-static int mc13xxx_probe(struct spi_device *spi)
+static int mc13xxx_common_init(struct mc13xxx *mc13xxx,
+ struct mc13xxx_platform_data *pdata, int irq);
+
+static void mc13xxx_common_cleanup(struct mc13xxx *mc13xxx);
+
+static int mc13xxx_spi_probe(struct spi_device *spi)
{
const struct of_device_id *of_id;
struct spi_driver *sdrv = to_spi_driver(spi->dev.driver);
struct mc13xxx *mc13xxx;
struct mc13xxx_platform_data *pdata = dev_get_platdata(&spi->dev);
- enum mc13xxx_id id;
int ret;

of_id = of_match_device(mc13xxx_dt_ids, &spi->dev);
@@ -768,13 +778,34 @@ static int mc13xxx_probe(struct spi_device *spi)
spi->bits_per_word = 32;
spi_setup(spi);

+ mc13xxx->dev = &spi->dev;
mc13xxx->spidev = spi;

+ ret = mc13xxx_common_init(mc13xxx, pdata, spi->irq);
+
+ if (ret) {
+ dev_set_drvdata(&spi->dev, NULL);
+ } else {
+ const struct spi_device_id *devid =
+ spi_get_device_id(mc13xxx->spidev);
+ if (!devid || devid->driver_data != mc13xxx->ictype)
+ dev_warn(mc13xxx->dev,
+ "device id doesn't match auto detection!\n");
+ }
+
+ return ret;
+}
+
+static int mc13xxx_common_init(struct mc13xxx *mc13xxx,
+ struct mc13xxx_platform_data *pdata, int irq)
+{
+ int ret;
+
mutex_init(&mc13xxx->lock);
mc13xxx_lock(mc13xxx);

- ret = mc13xxx_identify(mc13xxx, &id);
- if (ret || id == MC13XXX_ID_INVALID)
+ ret = mc13xxx_identify(mc13xxx);
+ if (ret)
goto err_revision;

/* mask all irqs */
@@ -786,18 +817,19 @@ static int mc13xxx_probe(struct spi_device *spi)
if (ret)
goto err_mask;

- ret = request_threaded_irq(spi->irq, NULL, mc13xxx_irq_thread,
+ ret = request_threaded_irq(irq, NULL, mc13xxx_irq_thread,
IRQF_ONESHOT | IRQF_TRIGGER_HIGH, "mc13xxx", mc13xxx);

if (ret) {
err_mask:
err_revision:
mc13xxx_unlock(mc13xxx);
- dev_set_drvdata(&spi->dev, NULL);
kfree(mc13xxx);
return ret;
}

+ mc13xxx->irq = irq;
+
mc13xxx_unlock(mc13xxx);

if (mc13xxx_probe_flags_dt(mc13xxx) < 0 && pdata)
@@ -831,39 +863,44 @@ err_revision:
return 0;
}

-static int __devexit mc13xxx_remove(struct spi_device *spi)
+static int __devexit mc13xxx_spi_remove(struct spi_device *spi)
{
struct mc13xxx *mc13xxx = dev_get_drvdata(&spi->dev);

- free_irq(mc13xxx->spidev->irq, mc13xxx);
+ mc13xxx_common_cleanup(mc13xxx);

- mfd_remove_devices(&spi->dev);
+ return 0;
+}

- kfree(mc13xxx);
+static void mc13xxx_common_cleanup(struct mc13xxx *mc13xxx)
+{
+ free_irq(mc13xxx->irq, mc13xxx);

- return 0;
+ mfd_remove_devices(mc13xxx->dev);
+
+ kfree(mc13xxx);
}

-static struct spi_driver mc13xxx_driver = {
+static struct spi_driver mc13xxx_spi_driver = {
.id_table = mc13xxx_device_id,
.driver = {
.name = "mc13xxx",
.owner = THIS_MODULE,
.of_match_table = mc13xxx_dt_ids,
},
- .probe = mc13xxx_probe,
- .remove = __devexit_p(mc13xxx_remove),
+ .probe = mc13xxx_spi_probe,
+ .remove = __devexit_p(mc13xxx_spi_remove),
};

static int __init mc13xxx_init(void)
{
- return spi_register_driver(&mc13xxx_driver);
+ return spi_register_driver(&mc13xxx_spi_driver);
}
subsys_initcall(mc13xxx_init);

static void __exit mc13xxx_exit(void)
{
- spi_unregister_driver(&mc13xxx_driver);
+ spi_unregister_driver(&mc13xxx_spi_driver);
}
module_exit(mc13xxx_exit);

--
1.7.3.4

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