Applied "regulator: qcom_spmi: Add support for SAW" to the regulator tree

[Mark Brown <broonie@kernel.org>]

The patch

   regulator: qcom_spmi: Add support for SAW

has been applied to the regulator tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 0caecaa87202b667591d57e8ca233ee1b548ba13 Mon Sep 17 00:00:00 2001
From: Ilia Lin <ilialin@codeaurora.org>
Date: Mon, 21 May 2018 14:25:30 +0300
Subject: [PATCH] regulator: qcom_spmi: Add support for SAW

Add support for SAW controlled regulators.
The regulators defined as SAW controlled in the device tree
will be controlled through special CPU registers instead of direct
SPMI accesses.
This is required especially for CPU supply regulators to synchronize
with clock scaling and for Automatic Voltage Switching.

Signed-off-by: Ilia Lin <ilialin@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/regulator/qcom_spmi-regulator.c | 133 +++++++++++++++++++++++-
 1 file changed, 130 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/qcom_spmi-regulator.c b/drivers/regulator/qcom_spmi-regulator.c
index 63c7a0c17777..9817f1a75342 100644
--- a/drivers/regulator/qcom_spmi-regulator.c
+++ b/drivers/regulator/qcom_spmi-regulator.c
@@ -25,6 +25,8 @@
 #include <linux/regulator/driver.h>
 #include <linux/regmap.h>
 #include <linux/list.h>
+#include <linux/mfd/syscon.h>
+#include <linux/io.h>
 
 /* Pin control enable input pins. */
 #define SPMI_REGULATOR_PIN_CTRL_ENABLE_NONE		0x00
@@ -181,6 +183,23 @@ enum spmi_boost_byp_registers {
 	SPMI_BOOST_BYP_REG_CURRENT_LIMIT	= 0x4b,
 };
 
+enum spmi_saw3_registers {
+	SAW3_SECURE				= 0x00,
+	SAW3_ID					= 0x04,
+	SAW3_SPM_STS				= 0x0C,
+	SAW3_AVS_STS				= 0x10,
+	SAW3_PMIC_STS				= 0x14,
+	SAW3_RST				= 0x18,
+	SAW3_VCTL				= 0x1C,
+	SAW3_AVS_CTL				= 0x20,
+	SAW3_AVS_LIMIT				= 0x24,
+	SAW3_AVS_DLY				= 0x28,
+	SAW3_AVS_HYSTERESIS			= 0x2C,
+	SAW3_SPM_STS2				= 0x38,
+	SAW3_SPM_PMIC_DATA_3			= 0x4C,
+	SAW3_VERSION				= 0xFD0,
+};
+
 /* Used for indexing into ctrl_reg.  These are offets from 0x40 */
 enum spmi_common_control_register_index {
 	SPMI_COMMON_IDX_VOLTAGE_RANGE		= 0,
@@ -1035,6 +1054,89 @@ static irqreturn_t spmi_regulator_vs_ocp_isr(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+#define SAW3_VCTL_DATA_MASK	0xFF
+#define SAW3_VCTL_CLEAR_MASK	0x700FF
+#define SAW3_AVS_CTL_EN_MASK	0x1
+#define SAW3_AVS_CTL_TGGL_MASK	0x8000000
+#define SAW3_AVS_CTL_CLEAR_MASK	0x7efc00
+
+static struct regmap *saw_regmap = NULL;
+
+static void spmi_saw_set_vdd(void *data)
+{
+	u32 vctl, data3, avs_ctl, pmic_sts;
+	bool avs_enabled = false;
+	unsigned long timeout;
+	u8 voltage_sel = *(u8 *)data;
+
+	regmap_read(saw_regmap, SAW3_AVS_CTL, &avs_ctl);
+	regmap_read(saw_regmap, SAW3_VCTL, &vctl);
+	regmap_read(saw_regmap, SAW3_SPM_PMIC_DATA_3, &data3);
+
+	/* select the band */
+	vctl &= ~SAW3_VCTL_CLEAR_MASK;
+	vctl |= (u32)voltage_sel;
+
+	data3 &= ~SAW3_VCTL_CLEAR_MASK;
+	data3 |= (u32)voltage_sel;
+
+	/* If AVS is enabled, switch it off during the voltage change */
+	avs_enabled = SAW3_AVS_CTL_EN_MASK & avs_ctl;
+	if (avs_enabled) {
+		avs_ctl &= ~SAW3_AVS_CTL_TGGL_MASK;
+		regmap_write(saw_regmap, SAW3_AVS_CTL, avs_ctl);
+	}
+
+	regmap_write(saw_regmap, SAW3_RST, 1);
+	regmap_write(saw_regmap, SAW3_VCTL, vctl);
+	regmap_write(saw_regmap, SAW3_SPM_PMIC_DATA_3, data3);
+
+	timeout = jiffies + usecs_to_jiffies(100);
+	do {
+		regmap_read(saw_regmap, SAW3_PMIC_STS, &pmic_sts);
+		pmic_sts &= SAW3_VCTL_DATA_MASK;
+		if (pmic_sts == (u32)voltage_sel)
+			break;
+
+		cpu_relax();
+
+	} while (time_before(jiffies, timeout));
+
+	/* After successful voltage change, switch the AVS back on */
+	if (avs_enabled) {
+		pmic_sts &= 0x3f;
+		avs_ctl &= ~SAW3_AVS_CTL_CLEAR_MASK;
+		avs_ctl |= ((pmic_sts - 4) << 10);
+		avs_ctl |= (pmic_sts << 17);
+		avs_ctl |= SAW3_AVS_CTL_TGGL_MASK;
+		regmap_write(saw_regmap, SAW3_AVS_CTL, avs_ctl);
+	}
+}
+
+static int
+spmi_regulator_saw_set_voltage(struct regulator_dev *rdev, unsigned selector)
+{
+	struct spmi_regulator *vreg = rdev_get_drvdata(rdev);
+	int ret;
+	u8 range_sel, voltage_sel;
+
+	ret = spmi_sw_selector_to_hw(vreg, selector, &range_sel, &voltage_sel);
+	if (ret)
+		return ret;
+
+	if (0 != range_sel) {
+		dev_dbg(&rdev->dev, "range_sel = %02X voltage_sel = %02X", \
+			range_sel, voltage_sel);
+		return -EINVAL;
+	}
+
+	/* Always do the SAW register writes on the first CPU */
+	return smp_call_function_single(0, spmi_saw_set_vdd, \
+					&voltage_sel, true);
+}
+
+static struct regulator_ops spmi_saw_ops = {};
+
 static struct regulator_ops spmi_smps_ops = {
 	.enable			= regulator_enable_regmap,
 	.disable		= regulator_disable_regmap,
@@ -1250,6 +1352,7 @@ static int spmi_regulator_match(struct spmi_regulator *vreg, u16 force_type)
 	}
 	dig_major_rev	= version[SPMI_COMMON_REG_DIG_MAJOR_REV
 					- SPMI_COMMON_REG_DIG_MAJOR_REV];
+
 	if (!force_type) {
 		type		= version[SPMI_COMMON_REG_TYPE -
 					  SPMI_COMMON_REG_DIG_MAJOR_REV];
@@ -1648,7 +1751,9 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 	struct regmap *regmap;
 	const char *name;
 	struct device *dev = &pdev->dev;
-	int ret;
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *syscon;
+	int ret, lenp;
 	struct list_head *vreg_list;
 
 	vreg_list = devm_kzalloc(dev, sizeof(*vreg_list), GFP_KERNEL);
@@ -1665,7 +1770,22 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 	if (!match)
 		return -ENODEV;
 
+	if (of_find_property(node, "qcom,saw-reg", &lenp)) {
+		syscon = of_parse_phandle(node, "qcom,saw-reg", 0);
+		saw_regmap = syscon_node_to_regmap(syscon);
+		of_node_put(syscon);
+		if (IS_ERR(regmap))
+			dev_err(dev, "ERROR reading SAW regmap\n");
+	}
+
 	for (reg = match->data; reg->name; reg++) {
+
+		if (saw_regmap && \
+		    of_find_property(of_find_node_by_name(node, reg->name), \
+				     "qcom,saw-slave", &lenp)) {
+			continue;
+		}
+
 		vreg = devm_kzalloc(dev, sizeof(*vreg), GFP_KERNEL);
 		if (!vreg)
 			return -ENOMEM;
@@ -1673,7 +1793,6 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 		vreg->dev = dev;
 		vreg->base = reg->base;
 		vreg->regmap = regmap;
-
 		if (reg->ocp) {
 			vreg->ocp_irq = platform_get_irq_byname(pdev, reg->ocp);
 			if (vreg->ocp_irq < 0) {
@@ -1681,7 +1800,6 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 				goto err;
 			}
 		}
-
 		vreg->desc.id = -1;
 		vreg->desc.owner = THIS_MODULE;
 		vreg->desc.type = REGULATOR_VOLTAGE;
@@ -1698,6 +1816,15 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 		if (ret)
 			continue;
 
+		if (saw_regmap && \
+		    of_find_property(of_find_node_by_name(node, reg->name), \
+				     "qcom,saw-leader", &lenp)) {
+			spmi_saw_ops = *(vreg->desc.ops);
+			spmi_saw_ops.set_voltage_sel = \
+				spmi_regulator_saw_set_voltage;
+			vreg->desc.ops = &spmi_saw_ops;
+		}
+
 		config.dev = dev;
 		config.driver_data = vreg;
 		config.regmap = regmap;
-- 
2.17.0