pmic: dm: Add support for MC34708 for PMIC DM

This patch adds support for MC34708 PMIC, to be used with driver model
(DM).

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/power/pmic/Kconfig

@@ -69,6 +69,13 @@ config DM_PMIC_MAX8998
 	This config enables implementation of driver-model pmic uclass features
 	for PMIC MAX8998. The driver implements read/write operations.
 
+config DM_PMIC_MC34708
+	bool "Enable Driver Model for PMIC MC34708"
+	depends on DM_PMIC
+	help
+	 This config enables implementation of driver-model pmic uclass features
+	 for PMIC MC34708. The driver implements read/write operations.
+
 config PMIC_MAX8997
 	bool "Enable Driver Model for PMIC MAX8997"
 	depends on DM_PMIC

drivers/power/pmic/Makefile

@@ -6,6 +6,7 @@
 obj-$(CONFIG_DM_PMIC) += pmic-uclass.o
 obj-$(CONFIG_DM_PMIC_MAX77686) += max77686.o
 obj-$(CONFIG_DM_PMIC_MAX8998) += max8998.o
+obj-$(CONFIG_DM_PMIC_MC34708) += mc34708.o
 obj-$(CONFIG_$(SPL_)DM_PMIC_PFUZE100) += pfuze100.o
 obj-$(CONFIG_PMIC_S2MPS11) += s2mps11.o
 obj-$(CONFIG_DM_PMIC_SANDBOX) += sandbox.o i2c_pmic_emul.o

drivers/power/pmic/mc34708.c

@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018
+ * Lukasz Majewski, DENX Software Engineering, lukma@denx.de
+ *
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fsl_pmic.h>
+#include <i2c.h>
+#include <power/pmic.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int mc34708_reg_count(struct udevice *dev)
+{
+	return PMIC_NUM_OF_REGS;
+}
+
+static int mc34708_write(struct udevice *dev, uint reg, const u8 *buff,
+			 int len)
+{
+	u8 buf[3] = { 0 };
+	int ret;
+
+	if (len != MC34708_TRANSFER_SIZE)
+		return -EINVAL;
+
+	/*
+	 * The MC34708 sends data with big endian format, hence we need to
+	 * perform manual byte swap.
+	 */
+	buf[0] = buff[2];
+	buf[1] = buff[1];
+	buf[2] = buff[0];
+
+	ret = dm_i2c_write(dev, reg, buf, len);
+	if (ret)
+		printf("write error to device: %p register: %#x!", dev, reg);
+
+	return ret;
+}
+
+static int mc34708_read(struct udevice *dev, uint reg, u8 *buff, int len)
+{
+	u8 buf[3] = { 0 };
+	int ret;
+
+	if (len != MC34708_TRANSFER_SIZE)
+		return -EINVAL;
+
+	ret = dm_i2c_read(dev, reg, buf, len);
+	if (ret)
+		printf("read error from device: %p register: %#x!", dev, reg);
+
+	buff[0] = buf[2];
+	buff[1] = buf[1];
+	buff[2] = buf[0];
+
+	return ret;
+}
+
+static int mc34708_probe(struct udevice *dev)
+{
+	struct uc_pmic_priv *priv = dev_get_uclass_priv(dev);
+
+	priv->trans_len = MC34708_TRANSFER_SIZE;
+
+	/*
+	 * Handle PMIC Errata 37: APS mode not fully functional,
+	 * use explicit PWM or PFM instead
+	 */
+	pmic_clrsetbits(dev, MC34708_REG_SW12_OPMODE,
+			MC34708_SW1AMODE_MASK | MC34708_SW2MODE_MASK,
+			SW_MODE_PWMPWM | (SW_MODE_PWMPWM << 14u));
+
+	pmic_clrsetbits(dev, MC34708_REG_SW345_OPMODE,
+			MC34708_SW3MODE_MASK | MC34708_SW4AMODE_MASK |
+			MC34708_SW4BMODE_MASK | MC34708_SW5MODE_MASK,
+			SW_MODE_PWMPWM | (SW_MODE_PWMPWM << 6u) |
+			(SW_MODE_PWMPWM << 12u) | (SW_MODE_PWMPWM << 18u));
+
+	return 0;
+}
+
+static struct dm_pmic_ops mc34708_ops = {
+	.reg_count = mc34708_reg_count,
+	.read	= mc34708_read,
+	.write	= mc34708_write,
+};
+
+static const struct udevice_id mc34708_ids[] = {
+	{ .compatible = "fsl,mc34708" },
+	{ }
+};
+
+U_BOOT_DRIVER(pmic_mc34708) = {
+	.name		= "mc34708_pmic",
+	.id		= UCLASS_PMIC,
+	.of_match	= mc34708_ids,
+	.probe          = mc34708_probe,
+	.ops		= &mc34708_ops,
+};