Merge tag 'staging-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO driver updates from Greg KH:
 "Here is the big staging/iio driver update for 5.4-rc1.

  Lots of churn here, with a few driver/filesystems moving out of
  staging finally:

     - erofs moved out of staging

     - greybus core code moved out of staging

  Along with that, a new filesytem has been added:

     - extfat

  to provide support for those devices requiring that filesystem (i.e.
  transfer devices to/from windows systems or printers)

  Other than that, there a number of new IIO drivers, and lots and lots
  and lots of staging driver cleanups and minor fixes as people continue
  to dig into those for easy changes.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (453 commits)
  Staging: gasket: Use temporaries to reduce line length.
  Staging: octeon: Avoid several usecases of strcpy
  staging: vhciq_core: replace snprintf with scnprintf
  staging: wilc1000: avoid twice IRQ handler execution for each single interrupt
  staging: wilc1000: remove unused interrupt status handling code
  staging: fbtft: make several arrays static const, makes object smaller
  staging: rtl8188eu: make two arrays static const, makes object smaller
  staging: rtl8723bs: core: Remove Macro "IS_MAC_ADDRESS_BROADCAST"
  dt-bindings: anybus-controller: move to staging/ tree
  staging: emxx_udc: remove local TRUE/FALSE definition
  staging: wilc1000: look for rtc_clk clock
  staging: dt-bindings: wilc1000: add optional rtc_clk property
  staging: nvec: make use of devm_platform_ioremap_resource
  staging: exfat: drop unused function parameter
  Staging: exfat: Avoid use of strcpy
  staging: exfat: use integer constants
  staging: exfat: cleanup spacing for casts
  staging: exfat: cleanup spacing for operators
  staging: rtl8723bs: hal: remove redundant variable n
  staging: pi433: Fix typo in documentation
  ...

1 files changed, 192 insertions, 2 deletions

diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index 1f7ce5186dfc..9b85fefc0a96 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -14,9 +14,11 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdesc.h>
 #include <linux/irqdomain.h>
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 
@@ -51,6 +53,17 @@
 
 #define STM32_ADC_CORE_SLEEP_DELAY_MS	2000
 
+/* SYSCFG registers */
+#define STM32MP1_SYSCFG_PMCSETR		0x04
+#define STM32MP1_SYSCFG_PMCCLRR		0x44
+
+/* SYSCFG bit fields */
+#define STM32MP1_SYSCFG_ANASWVDD_MASK	BIT(9)
+
+/* SYSCFG capability flags */
+#define HAS_VBOOSTER		BIT(0)
+#define HAS_ANASWVDD		BIT(1)
+
 /**
  * stm32_adc_common_regs - stm32 common registers, compatible dependent data
  * @csr:	common status register offset
@@ -74,11 +87,13 @@ struct stm32_adc_priv;
  * @regs:	common registers for all instances
  * @clk_sel:	clock selection routine
  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
+ * @has_syscfg: SYSCFG capability flags
  */
 struct stm32_adc_priv_cfg {
 	const struct stm32_adc_common_regs *regs;
 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
 	u32 max_clk_rate_hz;
+	unsigned int has_syscfg;
 };
 
 /**
@@ -87,22 +102,32 @@ struct stm32_adc_priv_cfg {
  * @domain:		irq domain reference
  * @aclk:		clock reference for the analog circuitry
  * @bclk:		bus clock common for all ADCs, depends on part used
+ * @booster:		booster supply reference
+ * @vdd:		vdd supply reference
  * @vdda:		vdda analog supply reference
  * @vref:		regulator reference
+ * @vdd_uv:		vdd supply voltage (microvolts)
+ * @vdda_uv:		vdda supply voltage (microvolts)
  * @cfg:		compatible configuration data
  * @common:		common data for all ADC instances
  * @ccr_bak:		backup CCR in low power mode
+ * @syscfg:		reference to syscon, system control registers
  */
 struct stm32_adc_priv {
 	int				irq[STM32_ADC_MAX_ADCS];
 	struct irq_domain		*domain;
 	struct clk			*aclk;
 	struct clk			*bclk;
+	struct regulator		*booster;
+	struct regulator		*vdd;
 	struct regulator		*vdda;
 	struct regulator		*vref;
+	int				vdd_uv;
+	int				vdda_uv;
 	const struct stm32_adc_priv_cfg	*cfg;
 	struct stm32_adc_common		common;
 	u32				ccr_bak;
+	struct regmap			*syscfg;
 };
 
 static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
@@ -349,7 +374,6 @@ static int stm32_adc_irq_probe(struct platform_device *pdev,
 			 */
 			if (i && priv->irq[i] == -ENXIO)
 				continue;
-			dev_err(&pdev->dev, "failed to get irq\n");
 
 			return priv->irq[i];
 		}
@@ -390,6 +414,82 @@ static void stm32_adc_irq_remove(struct platform_device *pdev,
 	}
 }
 
+static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
+					     struct device *dev)
+{
+	int ret;
+
+	/*
+	 * On STM32H7 and STM32MP1, the ADC inputs are multiplexed with analog
+	 * switches (via PCSEL) which have reduced performances when their
+	 * supply is below 2.7V (vdda by default):
+	 * - Voltage booster can be used, to get full ADC performances
+	 *   (increases power consumption).
+	 * - Vdd can be used to supply them, if above 2.7V (STM32MP1 only).
+	 *
+	 * Recommended settings for ANASWVDD and EN_BOOSTER:
+	 * - vdda < 2.7V but vdd > 2.7V: ANASWVDD = 1, EN_BOOSTER = 0 (stm32mp1)
+	 * - vdda < 2.7V and vdd < 2.7V: ANASWVDD = 0, EN_BOOSTER = 1
+	 * - vdda >= 2.7V:               ANASWVDD = 0, EN_BOOSTER = 0 (default)
+	 */
+	if (priv->vdda_uv < 2700000) {
+		if (priv->syscfg && priv->vdd_uv > 2700000) {
+			ret = regulator_enable(priv->vdd);
+			if (ret < 0) {
+				dev_err(dev, "vdd enable failed %d\n", ret);
+				return ret;
+			}
+
+			ret = regmap_write(priv->syscfg,
+					   STM32MP1_SYSCFG_PMCSETR,
+					   STM32MP1_SYSCFG_ANASWVDD_MASK);
+			if (ret < 0) {
+				regulator_disable(priv->vdd);
+				dev_err(dev, "vdd select failed, %d\n", ret);
+				return ret;
+			}
+			dev_dbg(dev, "analog switches supplied by vdd\n");
+
+			return 0;
+		}
+
+		if (priv->booster) {
+			/*
+			 * This is optional, as this is a trade-off between
+			 * analog performance and power consumption.
+			 */
+			ret = regulator_enable(priv->booster);
+			if (ret < 0) {
+				dev_err(dev, "booster enable failed %d\n", ret);
+				return ret;
+			}
+			dev_dbg(dev, "analog switches supplied by booster\n");
+
+			return 0;
+		}
+	}
+
+	/* Fallback using vdda (default), nothing to do */
+	dev_dbg(dev, "analog switches supplied by vdda (%d uV)\n",
+		priv->vdda_uv);
+
+	return 0;
+}
+
+static void stm32_adc_core_switches_supply_dis(struct stm32_adc_priv *priv)
+{
+	if (priv->vdda_uv < 2700000) {
+		if (priv->syscfg && priv->vdd_uv > 2700000) {
+			regmap_write(priv->syscfg, STM32MP1_SYSCFG_PMCCLRR,
+				     STM32MP1_SYSCFG_ANASWVDD_MASK);
+			regulator_disable(priv->vdd);
+			return;
+		}
+		if (priv->booster)
+			regulator_disable(priv->booster);
+	}
+}
+
 static int stm32_adc_core_hw_start(struct device *dev)
 {
 	struct stm32_adc_common *common = dev_get_drvdata(dev);
@@ -402,10 +502,21 @@ static int stm32_adc_core_hw_start(struct device *dev)
 		return ret;
 	}
 
+	ret = regulator_get_voltage(priv->vdda);
+	if (ret < 0) {
+		dev_err(dev, "vdda get voltage failed, %d\n", ret);
+		goto err_vdda_disable;
+	}
+	priv->vdda_uv = ret;
+
+	ret = stm32_adc_core_switches_supply_en(priv, dev);
+	if (ret < 0)
+		goto err_vdda_disable;
+
 	ret = regulator_enable(priv->vref);
 	if (ret < 0) {
 		dev_err(dev, "vref enable failed\n");
-		goto err_vdda_disable;
+		goto err_switches_dis;
 	}
 
 	if (priv->bclk) {
@@ -433,6 +544,8 @@ err_bclk_disable:
 		clk_disable_unprepare(priv->bclk);
 err_regulator_disable:
 	regulator_disable(priv->vref);
+err_switches_dis:
+	stm32_adc_core_switches_supply_dis(priv);
 err_vdda_disable:
 	regulator_disable(priv->vdda);
 
@@ -451,9 +564,80 @@ static void stm32_adc_core_hw_stop(struct device *dev)
 	if (priv->bclk)
 		clk_disable_unprepare(priv->bclk);
 	regulator_disable(priv->vref);
+	stm32_adc_core_switches_supply_dis(priv);
 	regulator_disable(priv->vdda);
 }
 
+static int stm32_adc_core_switches_probe(struct device *dev,
+					 struct stm32_adc_priv *priv)
+{
+	struct device_node *np = dev->of_node;
+	int ret;
+
+	/* Analog switches supply can be controlled by syscfg (optional) */
+	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+	if (IS_ERR(priv->syscfg)) {
+		ret = PTR_ERR(priv->syscfg);
+		if (ret != -ENODEV) {
+			if (ret != -EPROBE_DEFER)
+				dev_err(dev, "Can't probe syscfg: %d\n", ret);
+			return ret;
+		}
+		priv->syscfg = NULL;
+	}
+
+	/* Booster can be used to supply analog switches (optional) */
+	if (priv->cfg->has_syscfg & HAS_VBOOSTER &&
+	    of_property_read_bool(np, "booster-supply")) {
+		priv->booster = devm_regulator_get_optional(dev, "booster");
+		if (IS_ERR(priv->booster)) {
+			ret = PTR_ERR(priv->booster);
+			if (ret != -ENODEV) {
+				if (ret != -EPROBE_DEFER)
+					dev_err(dev, "can't get booster %d\n",
+						ret);
+				return ret;
+			}
+			priv->booster = NULL;
+		}
+	}
+
+	/* Vdd can be used to supply analog switches (optional) */
+	if (priv->cfg->has_syscfg & HAS_ANASWVDD &&
+	    of_property_read_bool(np, "vdd-supply")) {
+		priv->vdd = devm_regulator_get_optional(dev, "vdd");
+		if (IS_ERR(priv->vdd)) {
+			ret = PTR_ERR(priv->vdd);
+			if (ret != -ENODEV) {
+				if (ret != -EPROBE_DEFER)
+					dev_err(dev, "can't get vdd %d\n", ret);
+				return ret;
+			}
+			priv->vdd = NULL;
+		}
+	}
+
+	if (priv->vdd) {
+		ret = regulator_enable(priv->vdd);
+		if (ret < 0) {
+			dev_err(dev, "vdd enable failed %d\n", ret);
+			return ret;
+		}
+
+		ret = regulator_get_voltage(priv->vdd);
+		if (ret < 0) {
+			dev_err(dev, "vdd get voltage failed %d\n", ret);
+			regulator_disable(priv->vdd);
+			return ret;
+		}
+		priv->vdd_uv = ret;
+
+		regulator_disable(priv->vdd);
+	}
+
+	return 0;
+}
+
 static int stm32_adc_probe(struct platform_device *pdev)
 {
 	struct stm32_adc_priv *priv;
@@ -514,6 +698,10 @@ static int stm32_adc_probe(struct platform_device *pdev)
 		priv->bclk = NULL;
 	}
 
+	ret = stm32_adc_core_switches_probe(dev, priv);
+	if (ret)
+		return ret;
+
 	pm_runtime_get_noresume(dev);
 	pm_runtime_set_active(dev);
 	pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS);
@@ -611,12 +799,14 @@ static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
 	.regs = &stm32h7_adc_common_regs,
 	.clk_sel = stm32h7_adc_clk_sel,
 	.max_clk_rate_hz = 36000000,
+	.has_syscfg = HAS_VBOOSTER,
 };
 
 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
 	.regs = &stm32h7_adc_common_regs,
 	.clk_sel = stm32h7_adc_clk_sel,
 	.max_clk_rate_hz = 40000000,
+	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
 };
 
 static const struct of_device_id stm32_adc_of_match[] = {