Re: [PATCH 2/3] NFC: trf7970a: Add device tree option of 1.8 Volt IO voltage

[Geoff Lansberry]

Thanks Mark.   Should I resubmit patches with the requested edits today, or wait a bit for more comments?  What is the desired etiquette?

> On Dec 20, 2016, at 9:23 PM, Mark Greer <mgreer@xxxxxxxxxxxxxxx> wrote:
> 
>> On Tue, Dec 20, 2016 at 11:16:31AM -0500, Geoff Lansberry wrote:
>> From: Geoff Lansberry <geoff@xxxxxxxxx>
>> 
>> The TRF7970A has configuration options for supporting hardware designs
>> with 1.8 Volt or 3.3 Volt IO.   This commit adds a device tree option,
>> using a fixed regulator binding, for setting the io voltage to match
>> the hardware configuration. If no option is supplied it defaults to
>> 3.3 volt configuration.
> 
> Sign-off ??  Same comment for you other patches.
> 
> <time passes>
> 
> Okay I see you have it at the end of the patch.  It should be here.
> 'git commit -s' is your friend.
> 
>> ---
>> .../devicetree/bindings/net/nfc/trf7970a.txt       |  4 ++--
>> drivers/nfc/trf7970a.c                             | 28 +++++++++++++++++++++-
>> 2 files changed, 29 insertions(+), 3 deletions(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>> index e262ac1..b5777d8 100644
>> --- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>> +++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
>> @@ -21,9 +21,9 @@ Optional SoC Specific Properties:
>> - t5t-rmb-extra-byte-quirk: Specify that the trf7970a has the erratum
>>   where an extra byte is returned by Read Multiple Block commands issued
>>   to Type 5 tags.
>> +- vdd-io-supply: Regulator specifying voltage for vdd-io
>> - clock-frequency: Set to specify that the input frequency to the trf7970a is 13560000Hz or 27120000Hz
>> 
>> -
>> Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>> 
>> &spi1 {
>> @@ -41,11 +41,11 @@ Example (for ARM-based BeagleBone with TRF7970A on SPI1):
>>                  <&gpio2 5 GPIO_ACTIVE_LOW>;
>>        vin-supply = <&ldo3_reg>;
>>        vin-voltage-override = <5000000>;
>> +        vdd-io-supply = <&ldo2_reg>;
>>        autosuspend-delay = <30000>;
>>        irq-status-read-quirk;
>>        en2-rf-quirk;
>>        t5t-rmb-extra-byte-quirk;
>> -        vdd_io_1v8;
> 
> It was already mentioned but this shouldn't have been added in the
> previous patch so it shouldn't be here now.
> 
>>        clock-frequency = <27120000>;
>>        status = "okay";
>>    };
>> diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
>> index 4e051e9..8a88195 100644
>> --- a/drivers/nfc/trf7970a.c
>> +++ b/drivers/nfc/trf7970a.c
> 
>> @@ -2062,6 +2068,7 @@ static int trf7970a_probe(struct spi_device *spi)
>>        return ret;
>>    }
>> 
>> +
> 
> Please don't add an extra blank line.
> 
>>    of_property_read_u32(np, "clock-frequency", &clk_freq);
>>    if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
>>        (clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY)) {
>> @@ -2105,6 +2112,25 @@ static int trf7970a_probe(struct spi_device *spi)
>>    if (uvolts > 4000000)
>>        trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
>> 
>> +    trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
>> +    if (IS_ERR(trf->regulator)) {
>> +        ret = PTR_ERR(trf->regulator);
>> +        dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
>> +        goto err_destroy_lock;
>> +    }
>> +
>> +    ret = regulator_enable(trf->regulator);
>> +    if (ret) {
>> +        dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
>> +        goto err_destroy_lock;
>> +    }
>> +
>> +
> 
> Please don't add an extra blank line.
> 
>> +    if (regulator_get_voltage(trf->regulator) == 1800000) {
>> +        trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
>> +        dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
>> +    }
>> +
>>    trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
>>            TRF7970A_SUPPORTED_PROTOCOLS,
>>            NFC_DIGITAL_DRV_CAPS_IN_CRC |
>> -- 
>> Signed-off-by: Geoff Lansberry <geoff@xxxxxxxxx>
> 
> Your 'Signed-off-by:' goes at the end of the commit description not here.
> 
> Overall, I think you did the right thing (unless someone disagrees).
> Just some minor issues.
> 
> Mark
> --