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

[Balaji T K]

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);
+	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;
 }
 
@@ -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;
+}
+
 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);
-- 
1.7.5.4