[PATCH v2 1/1] mfd: intel_quark_i2c_gpio: Add Intel Quark X1000 I2C-GPIO MFD Driver

Raymond Tan
2014-11-11T13:46:56Z

In Quark X1000, there's a single PCI device that provides both
an I2C controller and a GPIO controller. This MFD driver will
split the 2 devices for their respective drivers.

This patch is based on Josef Ahmad's initial work for Quark enabling.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Weike Chen <alvin.chen@intel.com>
Signed-off-by: Raymond Tan <raymond.tan@intel.com>
---
drivers/mfd/Kconfig | 11 ++
drivers/mfd/Makefile | 1 +
drivers/mfd/intel_quark_i2c_gpio.c | 298 ++++++++++++++++++++++++++++++++++++
3 files changed, 310 insertions(+)
create mode 100644 drivers/mfd/intel_quark_i2c_gpio.c

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index b7c74a7..d01d042 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -219,6 +219,17 @@ config HTC_I2CPLD
This device provides input and output GPIOs through an I2C
interface to one or more sub-chips.

+config MFD_INTEL_QUARK_I2C_GPIO
+ tristate "Intel Quark MFD I2C GPIO"
+ depends on PCI && X86
+ depends on COMMON_CLK
+ select MFD_CORE
+ help
+ This MFD provides support for I2C and GPIO that exist only
+ in a single PCI device. It splits the 2 IO devices to
+ their respective IO driver.
+ The GPIO exports a total amount of 8 interrupt-capable GPIOs.
+
config LPC_ICH
tristate "Intel ICH LPC"
depends on PCI
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 8a28dc9..d42652d 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -133,6 +133,7 @@ obj-$(CONFIG_AB8500_CORE) += ab8500-core.o ab8500-sysctrl.o
obj-$(CONFIG_MFD_TIMBERDALE) += timberdale.o
obj-$(CONFIG_PMIC_ADP5520) += adp5520.o
obj-$(CONFIG_MFD_KEMPLD) += kempld-core.o
+obj-$(CONFIG_MFD_INTEL_QUARK_I2C_GPIO) += intel_quark_i2c_gpio.o
obj-$(CONFIG_LPC_SCH) += lpc_sch.o
obj-$(CONFIG_LPC_ICH) += lpc_ich.o
obj-$(CONFIG_MFD_RDC321X) += rdc321x-southbridge.o
diff --git a/drivers/mfd/intel_quark_i2c_gpio.c b/drivers/mfd/intel_quark_i2c_gpio.c
new file mode 100644
index 0000000..eed95da
--- /dev/null
+++ b/drivers/mfd/intel_quark_i2c_gpio.c
@@ -0,0 +1,298 @@
+/*
+ * Intel Quark MFD PCI driver for I2C & GPIO
+ *
+ * Copyright(c) 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * Intel Quark PCI device for I2C and GPIO controller sharing the same
+ * PCI function. This PCI driver will split the 2 devices into their
+ * respective drivers.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/mfd/core.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/dmi.h>
+#include <linux/platform_data/gpio-dwapb.h>
+#include <linux/platform_data/i2c-designware.h>
+
+/* PCI BAR for register base address */
+#define MFD_I2C_BAR 0
+#define MFD_GPIO_BAR 1
+
+/* The base GPIO number under GPIOLIB framework */
+#define INTEL_QUARK_MFD_GPIO_BASE 8
+
+/* The default number of South-Cluster GPIO on Quark. */
+#define INTEL_QUARK_MFD_NGPIO 8
+
+/* The DesignWare GPIO ports on Quark. */
+#define INTEL_QUARK_GPIO_NPORTS 1
+
+#define INTEL_QUARK_IORES_MEM 0
+#define INTEL_QUARK_IORES_IRQ 1
+
+#define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
+
+/* The Quark I2C controller source clock */
+#define INTEL_QUARK_I2C_CLK_HZ 33000000
+
+#define INTEL_QUARK_I2C_NCLK 1
+
+struct clk *intel_quark_i2c_clk;
+struct clk_lookup *intel_quark_i2c_clk_lookups;
+
+struct i2c_mode_info {
+ const char *name;
+ unsigned int i2c_scl_freq;
+};
+
+static const struct i2c_mode_info platform_i2c_mode_info[] = {
+ {
+ .name = "Galileo",
+ .i2c_scl_freq = 100000,
+ },
+ {
+ .name = "GalileoGen2",
+ .i2c_scl_freq = 400000,
+ },
+};
+
+static struct resource intel_quark_i2c_res[] = {
+ [INTEL_QUARK_IORES_MEM] = {
+ .flags = IORESOURCE_MEM,
+ },
+ [INTEL_QUARK_IORES_IRQ] = {
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct resource intel_quark_gpio_res[] = {
+ [INTEL_QUARK_IORES_MEM] = {
+ .flags = IORESOURCE_MEM,
+ },
+};
+
+static struct mfd_cell intel_quark_mfd_cells[] = {
+ {
+ .id = MFD_I2C_BAR,
+ .name = "i2c_designware",
+ .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
+ .resources = intel_quark_i2c_res,
+ .ignore_resource_conflicts = true,
+ },
+ {
+ .id = MFD_GPIO_BAR,
+ .name = "gpio-dwapb",
+ .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
+ .resources = intel_quark_gpio_res,
+ .ignore_resource_conflicts = true,
+ },
+};
+
+static const struct pci_device_id intel_quark_mfd_ids[] = {
+ { PCI_VDEVICE(INTEL, 0x0934), },
+ { 0,}
+};
+MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
+
+static struct dwapb_platform_data *
+intel_quark_prepare_pdata(struct pci_dev *pdev)
+{
+ struct dwapb_platform_data *pdata;
+ struct device *dev = &pdev->dev;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ /* For intel quark x1000, it has only one port: portA */
+ pdata->nports = INTEL_QUARK_GPIO_NPORTS;
+ pdata->properties = devm_kcalloc(dev, pdata->nports,
+ sizeof(*pdata->properties),
+ GFP_KERNEL);
+ if (!pdata->properties)
+ return ERR_PTR(-ENOMEM);
+
+ /* Set the properties for portA */
+ pdata->properties->node = NULL;
+ pdata->properties->name = "intel-quark-x1000-gpio-portA";
+ pdata->properties->idx = 0;
+ pdata->properties->ngpio = INTEL_QUARK_MFD_NGPIO;
+ pdata->properties->gpio_base = INTEL_QUARK_MFD_GPIO_BASE;
+ pdata->properties->irq = pdev->irq;
+ pdata->properties->irq_shared = true;
+
+ return pdata;
+}
+
+static struct dw_i2c_platform_data *
+intel_quark_get_i2c_mode(struct pci_dev *pdev)
+{
+ const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
+ struct dw_i2c_platform_data *pdata;
+ struct device *dev = &pdev->dev;
+ unsigned int i;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ /* Fast mode by default */
+ pdata->i2c_scl_freq = 400000;
+
+ for (i = 0; i < ARRAY_SIZE(platform_i2c_mode_info); i++)
+ if (!strcmp(board_name, platform_i2c_mode_info[i].name))
+ pdata->i2c_scl_freq
+ = platform_i2c_mode_info[i].i2c_scl_freq;
+
+ return pdata;
+}
+
+static int intel_quark_register_i2c_clk(struct pci_dev *pdev)
+{
+ intel_quark_i2c_clk_lookups = devm_kcalloc(
+ &pdev->dev, INTEL_QUARK_I2C_NCLK,
+ sizeof(*intel_quark_i2c_clk_lookups), GFP_KERNEL);
+
+ if (!intel_quark_i2c_clk_lookups)
+ return -ENOMEM;
+
+ intel_quark_i2c_clk_lookups[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
+
+ intel_quark_i2c_clk = clk_register_fixed_rate(
+ &pdev->dev, INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
+ CLK_IS_ROOT, INTEL_QUARK_I2C_CLK_HZ);
+
+ return clk_register_clkdevs(intel_quark_i2c_clk,
+ intel_quark_i2c_clk_lookups, INTEL_QUARK_I2C_NCLK);
+}
+
+static void intel_quark_unregister_i2c_clk(void)
+{
+ if (!intel_quark_i2c_clk || !intel_quark_i2c_clk_lookups)
+ return;
+
+ clkdev_drop(intel_quark_i2c_clk_lookups);
+ clk_unregister(intel_quark_i2c_clk);
+}
+
+static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
+{
+ struct dw_i2c_platform_data *pdata;
+ struct resource *res = (struct resource *)cell->resources;
+ int retval;
+
+ res[INTEL_QUARK_IORES_MEM].start =
+ pci_resource_start(pdev, MFD_I2C_BAR);
+ res[INTEL_QUARK_IORES_MEM].end =
+ pci_resource_end(pdev, MFD_I2C_BAR);
+
+ res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
+ res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
+
+ retval = intel_quark_register_i2c_clk(pdev);
+ if (retval) {
+ dev_err(&pdev->dev, "Fixed clk register failed: %d\n", retval);
+ return retval;
+ }
+
+ pdata = intel_quark_get_i2c_mode(pdev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+
+ cell->platform_data = pdata;
+ cell->pdata_size = sizeof(*pdata);
+
+ return 0;
+}
+
+static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
+{
+ struct dwapb_platform_data *pdata;
+ struct resource *res = (struct resource *)cell->resources;
+
+ res[INTEL_QUARK_IORES_MEM].start =
+ pci_resource_start(pdev, MFD_GPIO_BAR);
+ res[INTEL_QUARK_IORES_MEM].end =
+ pci_resource_end(pdev, MFD_GPIO_BAR);
+
+ pdata = intel_quark_prepare_pdata(pdev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+
+ cell->platform_data = pdata;
+ cell->pdata_size = sizeof(*pdata);
+
+ return 0;
+}
+
+struct intel_quark_mfd_dev {
+ int (*setup)(struct pci_dev *pdev, struct mfd_cell *cell);
+ struct mfd_cell *cell;
+};
+
+static struct intel_quark_mfd_dev intel_quark_mfd_devs[] = {
+ {
+ .cell = &intel_quark_mfd_cells[MFD_I2C_BAR],
+ .setup = intel_quark_i2c_setup,
+ },
+ {
+ .cell = &intel_quark_mfd_cells[MFD_GPIO_BAR],
+ .setup = intel_quark_gpio_setup,
+ },
+ {
+ /* terminator */
+ },
+};
+
+static int intel_quark_mfd_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct intel_quark_mfd_dev *mfd_dev;
+ int retval;
+
+ retval = pcim_enable_device(pdev);
+ if (retval)
+ return retval;
+
+ for (mfd_dev = intel_quark_mfd_devs; mfd_dev->cell; mfd_dev++)
+ if (mfd_dev->setup) {
+ retval = mfd_dev->setup(pdev, mfd_dev->cell);
+ if (retval)
+ return retval;
+ }
+
+ return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
+ ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0, NULL);
+}
+
+static void intel_quark_mfd_remove(struct pci_dev *pdev)
+{
+ intel_quark_unregister_i2c_clk();
+ mfd_remove_devices(&pdev->dev);
+}
+
+static struct pci_driver intel_quark_mfd_driver = {
+ .name = "intel_quark_mfd_i2c_gpio",
+ .id_table = intel_quark_mfd_ids,
+ .probe = intel_quark_mfd_probe,
+ .remove = intel_quark_mfd_remove,
+};
+
+module_pci_driver(intel_quark_mfd_driver);
+
+MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
+MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5