[PATCH 3/3] mfd: d1w: iproc: Add d1w driver
Scott Branden
scott.branden at broadcom.com
Wed Aug 16 10:45:25 PDT 2017
From: Shreesha Rajashekar <shreesha at broadcom.com>
d1w bus master controller is added as a mfd node.
ds1wm driver is hooked to this node through the mfd framework.
Signed-off-by: Shreesha Rajashekar <shreesha at broadcom.com>
Signed-off-by: Scott Branden <scott.branden at broadcom.com>
---
drivers/mfd/Kconfig | 11 +++
drivers/mfd/Makefile | 1 +
drivers/mfd/bcm-iproc-d1w.c | 202 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 214 insertions(+)
create mode 100644 drivers/mfd/bcm-iproc-d1w.c
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 94ad2c1..a7d9335 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -216,6 +216,17 @@ config MFD_ASIC3
This driver supports the ASIC3 multifunction chip found on many
PDAs (mainly iPAQ and HTC based ones)
+config MFD_IPROC_D1W
+ bool "IPROC DS1WM one wire interface"
+ depends on (ARCH_BCM_IPROC || COMPILE_TEST)
+ select MFD_CORE
+ default ARCH_BCM_IPROC
+ help
+ This driver provides support to the Dallas One Wire (D1W).This block
+ is found in various Broadcom iProc family of SoCs.
+ The Cygnus Dallas 1-Wire Interface provides complete
+ control of the 1-Wire bus through 8-bit commands.
+
config PMIC_DA903X
bool "Dialog Semiconductor DA9030/DA9034 PMIC Support"
depends on I2C=y
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 080793b..2f39fdd 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -217,6 +217,7 @@ obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o
obj-$(CONFIG_INTEL_SOC_PMIC_BXTWC) += intel_soc_pmic_bxtwc.o
obj-$(CONFIG_INTEL_SOC_PMIC_CHTWC) += intel_soc_pmic_chtwc.o
obj-$(CONFIG_MFD_MT6397) += mt6397-core.o
+obj-$(CONFIG_MFD_IPROC_D1W) += bcm-iproc-d1w.o
obj-$(CONFIG_MFD_ALTERA_A10SR) += altera-a10sr.o
obj-$(CONFIG_MFD_SUN4I_GPADC) += sun4i-gpadc.o
diff --git a/drivers/mfd/bcm-iproc-d1w.c b/drivers/mfd/bcm-iproc-d1w.c
new file mode 100644
index 0000000..d439060
--- /dev/null
+++ b/drivers/mfd/bcm-iproc-d1w.c
@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2016 Broadcom.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/stddef.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/ds1wm.h>
+
+#define D1W_DIN_OFFSET 0x00
+#define D1W_DOUT_OFFSET 0x04
+#define D1W_ADDR_OFFSET 0x08
+#define D1W_CTRL_OFFSET 0x0C
+
+#define WRITE_CMD 0x3
+#define READ_CMD 0x2
+
+#define DEFAULT_RESET_RECOVERY_DELAY 1
+/* CLOCK_RATE programmed in the IP divisor register DS1WM_CLKDIV*/
+#define DEFAULT_CLOCK_RATE 100000000
+
+struct iproc_ds1wm_core {
+ struct ds1wm_driver_data plat_data;
+ struct clk *ds1wm_clk;
+};
+
+static void iproc_d1w_write_register(void __iomem *base, u32 reg,
+ u8 val)
+{
+ writel(val, base + D1W_DIN_OFFSET);
+ writel(reg, base + D1W_ADDR_OFFSET);
+ writel(WRITE_CMD, base + D1W_CTRL_OFFSET);
+}
+
+static u8 iproc_d1w_read_register(void __iomem *base, u32 reg)
+{
+ writel(reg, base + D1W_ADDR_OFFSET);
+ writel(READ_CMD, base + D1W_CTRL_OFFSET);
+ return readb(base + D1W_DOUT_OFFSET);
+}
+
+static int iproc_ds1wm_enable(struct platform_device *pdev)
+{
+ struct iproc_ds1wm_core *ds1wm_core;
+
+ ds1wm_core = dev_get_drvdata(pdev->dev.parent);
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ if (ds1wm_core->ds1wm_clk)
+ return clk_prepare_enable(ds1wm_core->ds1wm_clk);
+
+ return 0;
+}
+
+static int iproc_ds1wm_disable(struct platform_device *pdev)
+{
+ struct iproc_ds1wm_core *ds1wm_core;
+
+ ds1wm_core = dev_get_drvdata(pdev->dev.parent);
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+ if (ds1wm_core->ds1wm_clk)
+ clk_disable_unprepare(ds1wm_core->ds1wm_clk);
+
+ return 0;
+}
+
+static struct resource iproc_ds1wm_resources[] = {
+ [0] = {
+ .flags = IORESOURCE_MEM,
+ },
+ [1] = {
+ .flags = IORESOURCE_IRQ,
+ }
+};
+
+static struct mfd_cell iproc_ds1wm_mfd_cell = {
+ .name = "ds1wm",
+ .enable = iproc_ds1wm_enable,
+ .disable = iproc_ds1wm_disable,
+ .num_resources = ARRAY_SIZE(iproc_ds1wm_resources),
+ .resources = iproc_ds1wm_resources,
+};
+
+static int iproc_d1w_dt_binding(struct platform_device *pdev,
+ struct iproc_ds1wm_core *ds1wm_core)
+{
+ int ret;
+
+ ret = of_property_read_u32(pdev->dev.of_node,
+ "reset-recover-delay",
+ &ds1wm_core->plat_data.reset_recover_delay);
+ if (ret < 0)
+ ds1wm_core->plat_data.reset_recover_delay =
+ DEFAULT_RESET_RECOVERY_DELAY;
+
+ ret = of_property_read_u32(pdev->dev.of_node,
+ "clock-frequency", &ds1wm_core->plat_data.clock_rate);
+ if (ret < 0)
+ ds1wm_core->plat_data.clock_rate = DEFAULT_CLOCK_RATE;
+
+ ds1wm_core->ds1wm_clk = devm_clk_get(&pdev->dev, "iproc_d1w_clk");
+ if (IS_ERR(ds1wm_core->ds1wm_clk)) {
+ dev_info(&pdev->dev,
+ "No clock specified. Assuming it's enabled\n");
+ ds1wm_core->ds1wm_clk = NULL;
+ }
+ ret = clk_set_rate(ds1wm_core->ds1wm_clk,
+ ds1wm_core->plat_data.clock_rate);
+ if (ret)
+ dev_info(&pdev->dev,
+ "Failed to set to %u\n", ds1wm_core->plat_data.clock_rate);
+ return ret;
+}
+
+static int iproc_d1w_mfd_init(struct platform_device *pdev)
+{
+ struct resource *res;
+ int ret;
+ int irq;
+ struct iproc_ds1wm_core *ds1wm_core;
+
+ ds1wm_core = platform_get_drvdata(pdev);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "No Memory Resource specified\n");
+ return -ENODEV;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "No IRQ specified\n");
+ return irq;
+ }
+
+ ds1wm_core->plat_data.read = iproc_d1w_read_register;
+ ds1wm_core->plat_data.write = iproc_d1w_write_register;
+
+ ret = mfd_add_devices(&pdev->dev, pdev->id,
+ &iproc_ds1wm_mfd_cell, 1, res, irq, NULL);
+ if (ret < 0)
+ dev_err(&pdev->dev, "failed to register iproc_d1w mfd\n");
+
+ dev_dbg(&pdev->dev, "Added iproc_d1w mfd successfully\n");
+ return ret;
+}
+
+static int iproc_d1w_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct iproc_ds1wm_core *ds1wm_core;
+
+ ds1wm_core = devm_kzalloc(&pdev->dev,
+ sizeof(struct iproc_ds1wm_core), GFP_KERNEL);
+ if (!ds1wm_core)
+ return -ENOMEM;
+
+ ret = iproc_d1w_dt_binding(pdev, ds1wm_core);
+ if (ret) {
+ dev_err(&pdev->dev, "Probe failed\n");
+ return ret;
+ }
+
+ iproc_ds1wm_mfd_cell.platform_data = &ds1wm_core->plat_data;
+ iproc_ds1wm_mfd_cell.pdata_size = sizeof(struct ds1wm_driver_data);
+
+ platform_set_drvdata(pdev, ds1wm_core);
+ ret = iproc_d1w_mfd_init(pdev);
+
+ return ret;
+}
+
+static const struct of_device_id iproc_d1w_of_match[] = {
+ { .compatible = "brcm,iproc-d1w" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, iproc_d1w_of_match);
+
+static struct platform_driver iproc_d1w_driver = {
+ .driver = {
+ .name = "brcm,iproc-d1w",
+ .of_match_table = of_match_ptr(iproc_d1w_of_match),
+ },
+ .probe = iproc_d1w_probe,
+};
+module_platform_driver(iproc_d1w_driver);
+
+MODULE_AUTHOR("Broadcom");
+MODULE_DESCRIPTION("Broadcom one wire busmaster Driver");
+MODULE_LICENSE("GPL v2");
--
2.5.0
More information about the linux-arm-kernel
mailing list