[PATCH v2 06/10] mmc: omap_hsmmc: add support for pbias configuration in dt

[Balaji T K]

On Wednesday 12 June 2013 08:07 PM, Tony Lindgren wrote:
> * Balaji T K <balajitk at ti.com> [130606 12:20]:
>> PBIAS register configuration is based on the regulator voltage
>> which supplies these pbias cells, sd i/o pads.
>> With PBIAS register address and bit definitions different across
>> omap[3,4,5], Simplify PBIAS configuration under three different
>> regulator voltage levels - O V, 1.8 V, 3 V. Corresponding pinctrl states
>> are defined as pbias_off, pbias_1v8, pbias_3v.
>>
>> pinctrl state mmc_init is used for configuring speed mode, loopback clock
>> (in devconf0/devconf1/prog_io1 register for omap3) and pull strength
>> configuration (in control_mmc1 for omap4)
>>
>> Signed-off-by: Balaji T K <balajitk at ti.com>
>> ---
>>   drivers/mmc/host/omap_hsmmc.c |   83 ++++++++++++++++++++++++++++++++++++++--
>>   1 files changed, 78 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
>> index 533ced2..8dd1cd3 100644
>> --- a/drivers/mmc/host/omap_hsmmc.c
>> +++ b/drivers/mmc/host/omap_hsmmc.c
>> @@ -182,6 +182,9 @@ struct omap_hsmmc_host {
>>   	int			req_in_progress;
>>   	struct omap_hsmmc_next	next_data;
>>
>> +	struct pinctrl		*pinctrl;
>> +	struct pinctrl_state	*pbias_off, *pbias_1v8, *pbias_3v, *mmc_init;
>> +
>>   	struct	omap_mmc_platform_data	*pdata;
>>   	int needs_vmmc:1;
>>   	int needs_vmmc_aux:1;
>> @@ -267,6 +270,12 @@ static int omap_hsmmc_set_power(struct device *dev, int slot, int power_on,
>>   	if (mmc_slot(host).before_set_reg)
>>   		mmc_slot(host).before_set_reg(dev, slot, power_on, vdd);
>>
>> +	if (host->pinctrl && host->pbias_off) {
>> +		ret = pinctrl_select_state(host->pinctrl, host->pbias_off);
>> +		if (ret < 0)
>> +			dev_err(host->dev, "pinctrl pbias_off select error\n");
>> +	}
>> +
>>   	/*
>>   	 * Assume Vcc regulator is used only to power the card ... OMAP
>>   	 * VDDS is used to power the pins, optionally with a transceiver to
>> @@ -304,6 +313,25 @@ static int omap_hsmmc_set_power(struct device *dev, int slot, int power_on,
>>   	if (mmc_slot(host).after_set_reg)
>>   		mmc_slot(host).after_set_reg(dev, slot, power_on, vdd);
>>
>> +	/* 100ms delay required for PBIAS configuration */
>> +	msleep(100);
>
> Hmm, why is the delay needed before the configuration? Is this something
> you could avoid by reading the pinconf state maybe?

This delay is needed for regulator voltage to stabilize.

>
>> +	if (!vdd && host->pinctrl && host->pbias_off) {
>> +		ret = pinctrl_select_state(host->pinctrl, host->pbias_off);
>> +		if (ret < 0)
>> +			dev_err(host->dev, "pinctrl pbias_off select error\n");
>> +	} else if (((1 << vdd) <= MMC_VDD_165_195) && host->pinctrl &&
>> +			host->pbias_1v8) {
>> +		ret = pinctrl_select_state(host->pinctrl, host->pbias_1v8);
>> +		if (ret < 0)
>> +			dev_err(host->dev, "pinctrl pbias_1v8 select error\n");
>> +	} else if (((1 << vdd) > MMC_VDD_165_195) && host->pinctrl &&
>> +			host->pbias_3v) {
>> +		ret = pinctrl_select_state(host->pinctrl, host->pbias_3v);
>> +		if (ret < 0)
>> +			dev_err(host->dev, "pinctrl pbias_3v select error\n");
>> +	}
>> +	usleep_range(350, 400);
>> +
>>   	return ret;
>>   }
>
> Maybe add some macro for doing the if (((1 << vdd) <= MMC_VDD_165_195)... tests?

OK

>
>> @@ -1775,6 +1803,52 @@ static inline struct omap_mmc_platform_data
>>   }
>>   #endif
>>
>> +static int omap_hsmmc_pinctrl_init(struct omap_hsmmc_host *host)
>> +{
>> +	int ret = 0;
>> +
>> +	host->pinctrl = devm_pinctrl_get(host->dev);
>> +	if (IS_ERR(host->pinctrl)) {
>> +		host->pinctrl = NULL;
>> +		dev_warn(host->dev,
>> +			 "pins are not configured from the driver\n");
>> +		return 0;
>> +	}
>> +
>> +	host->mmc_init = pinctrl_lookup_state(host->pinctrl, "mmc_init");
>> +	if (IS_ERR(host->mmc_init)) {
>> +		dev_vdbg(host->dev, "optional: mmc_init lookup error");
>> +		host->mmc_init = NULL;
>> +	} else {
>> +		ret = pinctrl_select_state(host->pinctrl, host->mmc_init);
>> +		if (ret < 0) {
>> +			dev_err(host->dev, "pinctrl mmc_init select error\n");
>> +			goto err_pinctrl;
>> +		}
>> +	}
>> +
>> +	host->pbias_off = pinctrl_lookup_state(host->pinctrl, "pbias_off");
>> +	if (IS_ERR(host->pbias_off)) {
>> +		dev_vdbg(host->dev, "optional: pbias_off lookup error");
>> +		host->pbias_off = NULL;
>> +	}
>> +
>> +	host->pbias_1v8 = pinctrl_lookup_state(host->pinctrl, "pbias_1v8");
>> +	if (IS_ERR(host->pbias_1v8)) {
>> +		dev_vdbg(host->dev, "optional: pbias_1v8 lookup error");
>> +		host->pbias_1v8 = NULL;
>> +	}
>> +
>> +	host->pbias_3v = pinctrl_lookup_state(host->pinctrl, "pbias_3v");
>> +	if (IS_ERR(host->pbias_3v)) {
>> +		dev_vdbg(host->dev, "optional: pbias_3v lookup error");
>> +		host->pbias_3v = NULL;
>> +	}
>> +
>> +err_pinctrl:
>> +	return ret;
>> +}
>
> Linus W may have some comments on this, although this is not the standard
> muxing stuff. The "mmc_init" state pins should be added to just the regular
> default state? Note that you can have phandles to however many sets of
> pins there.

Yes, can add &mmc_init pin config to default state.

>
>>   static int omap_hsmmc_probe(struct platform_device *pdev)
>>   {
>>   	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
>> @@ -1785,7 +1859,6 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>>   	const struct of_device_id *match;
>>   	dma_cap_mask_t mask;
>>   	unsigned tx_req, rx_req;
>> -	struct pinctrl *pinctrl;
>>
>>   	match = of_match_device(of_match_ptr(omap_mmc_of_match), &pdev->dev);
>>   	if (match) {
>> @@ -2005,10 +2078,9 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>>
>>   	omap_hsmmc_disable_irq(host);
>>
>> -	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
>> -	if (IS_ERR(pinctrl))
>> -		dev_warn(&pdev->dev,
>> -			"pins are not configured from the driver\n");
>> +	ret = omap_hsmmc_pinctrl_init(host);
>> +	if (ret)
>> +		goto err_pinctrl_state;
>>
>>   	omap_hsmmc_protect_card(host);
>>
>> @@ -2034,6 +2106,7 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>>
>>   err_slot_name:
>>   	mmc_remove_host(mmc);
>> +err_pinctrl_state:
>>   	free_irq(mmc_slot(host).card_detect_irq, host);
>>   err_irq_cd:
>>   	omap_hsmmc_reg_put(host);
>
> Regards,
>
> Tony
>