Re: [PATCH 06/13] mfd: twl-core: Add initial DT support for twl4030/twl6030

Cousson, Benoit
2011-09-28T08:52:29Z

On 9/27/2011 7:42 AM, Nayak, Rajendra wrote:
> On Monday 26 September 2011 10:20 PM, Benoit Cousson wrote:
>> Add initial device-tree support for twl familly chips.
>
> s/familly/family

Oops.

>> The current version is missing the regulator entries due
>> to the lack of DT regulator bindings for the moment.
>> Only the simple sub-modules that do not depend on
>> platform_data information can be initialized properly.
>>
>> Add documentation for the Texas Instruments TWL Integrated Chip.
>>
>> Signed-off-by: Benoit Cousson<b-cousson@ti.com>
>> Cc: Balaji T K<balajitk@ti.com>
>> Cc: Graeme Gregory<gg@slimlogic.co.uk>
>> Cc: Samuel Ortiz<sameo@linux.intel.com>
>> ---
>> .../devicetree/bindings/mfd/twl-familly.txt | 47 +++++++++++++++++
>> drivers/mfd/twl-core.c | 53 ++++++++++++++++++--
>> 2 files changed, 96 insertions(+), 4 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/mfd/twl-familly.txt
>
> s/familly.txt/family.txt

At least I am consistent in my typos ;-)

>> diff --git a/Documentation/devicetree/bindings/mfd/twl-familly.txt b/Documentation/devicetree/bindings/mfd/twl-familly.txt
>> new file mode 100644
>> index 0000000..ff4cacd
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mfd/twl-familly.txt
>> @@ -0,0 +1,47 @@
>> +Texas Instruments TWL family
>> +
>> +The TWLs are Integrated Power Management Chips.
>> +Some version might contain much more analog function like
>> +USB transceiver or Audio amplifier.
>> +These chips are connected to an i2c bus.
>> +
>> +
>> +Required properties:
>> +- compatible : Must be "ti,twl4030";
>> + For Integrated power-management/audio CODEC device used in OMAP3
>> + based boards
>> +- compatible : Must be "ti,twl6030";
>> + For Integrated power-management used in OMAP4 based boards
>> +- interrupts : This i2c device has an IRQ line connected to the main SoC
>> +- interrupt-controller : Since the twl support several interrupts internally,
>> + it is considered as an interrupt controller cascaded to the SoC one.
>> +- #interrupt-cells =<1>;
>> +- interrupt-parent : The parent interrupt controller.
>> +
>> +Optional node:
>> +- Child nodes contain in the twl. The twl family is made of severals variants
>> + that support a different number of features.
>> + The children nodes will thus depend of the capabilty of the variant.
>> +
>> +
>> +Example:
>> +/*
>> + * Integrated Power Management Chip
>> + * http://www.ti.com/lit/ds/symlink/twl6030.pdf
>> + */
>> +twl@48 {
>> + compatible = "ti,twl6030";
>> + reg =<0x48>;
>
> What does the 'reg' property signify here for twl?

The i2c slave address.

>> + interrupts =<39>; /* IRQ_SYS_1N cascaded to gic */
>> + interrupt-controller;
>> + #interrupt-cells =<1>;
>> + interrupt-parent =<&gic>;
>> + #address-cells =<1>;
>> + #size-cells =<0>;
>> +
>> + twl_rtc {
>> + compatible = "ti,twl_rtc";
>> + interrupts =<11>;
>> + reg =<0>;
>
> Does the 'reg' property need to be faked for
> every twl child node, even if it does not have
> any?

No, it was even removed from the DTS. But I forgot to update the
documentation:-(

>> + };
>> +};
>> diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
>> index 01ecfee..3ef0b43 100644
>> --- a/drivers/mfd/twl-core.c
>> +++ b/drivers/mfd/twl-core.c
>> @@ -33,6 +33,10 @@
>> #include<linux/platform_device.h>
>> #include<linux/clk.h>
>> #include<linux/err.h>
>> +#include<linux/slab.h>
>> +#include<linux/of_irq.h>
>> +#include<linux/of_platform.h>
>> +#include<linux/irqdomain.h>
>>
>> #include<linux/regulator/machine.h>
>>
>> @@ -1182,22 +1186,53 @@ twl_probe(struct i2c_client *client, const struct i2c_device_id *id)
>> int status;
>> unsigned i;
>> struct twl4030_platform_data *pdata = client->dev.platform_data;
>> + struct device_node *node = client->dev.of_node;
>> u8 temp;
>> int ret = 0;
>>
>> + if (node&& !pdata) {
>> + /*
>> + * XXX: Temporary fake pdata until the information
>> + * is correctly retrieved by every TWL modules from DT.
>> + */
>> + pdata = kzalloc(sizeof(struct twl4030_platform_data),
>> + GFP_KERNEL);
>
> devm_kzalloc instead?

Good point.

>> + if (!pdata) {
>> + status = -ENOMEM;
>> + goto exit;
>> + }
>> +
>> + /*
>> + * XXX: For the moment the IRQs for TWL seems to be encoded in
>> + * the global OMAP space. That should be cleaned to allow
>> + * dynamically adding a new IRQ controller.
>> + */
>> + if ((id->driver_data)& TWL6030_CLASS) {
>> + pdata->irq_base = TWL6030_IRQ_BASE;
>> + pdata->irq_end = pdata->irq_base + TWL6030_BASE_NR_IRQS;
>> + } else {
>> + pdata->irq_base = TWL4030_IRQ_BASE;
>> + pdata->irq_end = pdata->irq_base + TWL4030_BASE_NR_IRQS;
>> + }
>> + irq_domain_add_simple(node, pdata->irq_base);
>> + }
>> +
>> if (!pdata) {
>> dev_dbg(&client->dev, "no platform data?\n");
>> - return -EINVAL;
>> + status = -EINVAL;
>> + goto fail_free;
>> }
>>
>> if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C) == 0) {
>> dev_dbg(&client->dev, "can't talk I2C?\n");
>> - return -EIO;
>> + status = -EIO;
>> + goto fail_free;
>> }
>>
>> if (inuse) {
>> dev_dbg(&client->dev, "driver is already in use\n");
>> - return -EBUSY;
>> + status = -EBUSY;
>> + goto fail_free;
>> }
>>
>> for (i = 0; i< TWL_NUM_SLAVES; i++) {
>> @@ -1269,10 +1304,20 @@ twl_probe(struct i2c_client *client, const struct i2c_device_id *id)
>> twl_i2c_write_u8(TWL4030_MODULE_INTBR, temp, REG_GPPUPDCTR1);
>> }
>>
>> - status = add_children(pdata, id->driver_data);
>> +#ifdef CONFIG_OF_DEVICE
>
> is the #ifdef really needed?

Yes, because the of_platform_populate does not have a stub in case of
none DT build... But I agree, it is ugly and the of_platform.h should
maybe be fixed instead.
I was too lazy to fix it :-)

Thanks,
Benoit