mfd: Add Intel MSIC driver
[firefly-linux-kernel-4.4.55.git] / drivers / mfd / intel_msic.c
diff --git a/drivers/mfd/intel_msic.c b/drivers/mfd/intel_msic.c
new file mode 100644 (file)
index 0000000..bd086b9
--- /dev/null
@@ -0,0 +1,501 @@
+/*
+ * Driver for Intel MSIC
+ *
+ * Copyright (C) 2011, Intel Corporation
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/gpio.h>
+#include <linux/module.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/intel_msic.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <asm/intel_scu_ipc.h>
+
+#define MSIC_VENDOR(id)                ((id >> 6) & 3)
+#define MSIC_VERSION(id)       (id & 0x3f)
+#define MSIC_MAJOR(id)         ('A' + ((id >> 3) & 7))
+#define MSIC_MINOR(id)         (id & 7)
+
+/*
+ * MSIC interrupt tree is readable from SRAM at INTEL_MSIC_IRQ_PHYS_BASE.
+ * Since IRQ block starts from address 0x002 we need to substract that from
+ * the actual IRQ status register address.
+ */
+#define MSIC_IRQ_STATUS(x)     (INTEL_MSIC_IRQ_PHYS_BASE + ((x) - 2))
+#define MSIC_IRQ_STATUS_ACCDET MSIC_IRQ_STATUS(INTEL_MSIC_ACCDET)
+
+/*
+ * The SCU hardware has limitation of 16 bytes per read/write buffer on
+ * Medfield.
+ */
+#define SCU_IPC_RWBUF_LIMIT    16
+
+/**
+ * struct intel_msic - an MSIC MFD instance
+ * @pdev: pointer to the platform device
+ * @vendor: vendor ID
+ * @version: chip version
+ * @irq_base: base address of the mapped MSIC SRAM interrupt tree
+ */
+struct intel_msic {
+       struct platform_device          *pdev;
+       unsigned                        vendor;
+       unsigned                        version;
+       void __iomem                    *irq_base;
+};
+
+static struct resource msic_touch_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_adc_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_battery_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_gpio_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_audio_resources[] = {
+       {
+               .name           = "IRQ",
+               .flags          = IORESOURCE_IRQ,
+       },
+       /*
+        * We will pass IRQ_BASE to the driver now but this can be removed
+        * when/if the driver starts to use intel_msic_irq_read().
+        */
+       {
+               .name           = "IRQ_BASE",
+               .flags          = IORESOURCE_MEM,
+               .start          = MSIC_IRQ_STATUS_ACCDET,
+               .end            = MSIC_IRQ_STATUS_ACCDET,
+       },
+};
+
+static struct resource msic_hdmi_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_thermal_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_power_btn_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+static struct resource msic_ocd_resources[] = {
+       {
+               .flags          = IORESOURCE_IRQ,
+       },
+};
+
+/*
+ * Devices that are part of the MSIC and are available via firmware
+ * populated SFI DEVS table.
+ */
+static struct mfd_cell msic_devs[] = {
+       [INTEL_MSIC_BLOCK_TOUCH]        = {
+               .name                   = "msic_touch",
+               .num_resources          = ARRAY_SIZE(msic_touch_resources),
+               .resources              = msic_touch_resources,
+       },
+       [INTEL_MSIC_BLOCK_ADC]          = {
+               .name                   = "msic_adc",
+               .num_resources          = ARRAY_SIZE(msic_adc_resources),
+               .resources              = msic_adc_resources,
+       },
+       [INTEL_MSIC_BLOCK_BATTERY]      = {
+               .name                   = "msic_battery",
+               .num_resources          = ARRAY_SIZE(msic_battery_resources),
+               .resources              = msic_battery_resources,
+       },
+       [INTEL_MSIC_BLOCK_GPIO]         = {
+               .name                   = "msic_gpio",
+               .num_resources          = ARRAY_SIZE(msic_gpio_resources),
+               .resources              = msic_gpio_resources,
+       },
+       [INTEL_MSIC_BLOCK_AUDIO]        = {
+               .name                   = "msic_audio",
+               .num_resources          = ARRAY_SIZE(msic_audio_resources),
+               .resources              = msic_audio_resources,
+       },
+       [INTEL_MSIC_BLOCK_HDMI]         = {
+               .name                   = "msic_hdmi",
+               .num_resources          = ARRAY_SIZE(msic_hdmi_resources),
+               .resources              = msic_hdmi_resources,
+       },
+       [INTEL_MSIC_BLOCK_THERMAL]      = {
+               .name                   = "msic_thermal",
+               .num_resources          = ARRAY_SIZE(msic_thermal_resources),
+               .resources              = msic_thermal_resources,
+       },
+       [INTEL_MSIC_BLOCK_POWER_BTN]    = {
+               .name                   = "msic_power_btn",
+               .num_resources          = ARRAY_SIZE(msic_power_btn_resources),
+               .resources              = msic_power_btn_resources,
+       },
+       [INTEL_MSIC_BLOCK_OCD]          = {
+               .name                   = "msic_ocd",
+               .num_resources          = ARRAY_SIZE(msic_ocd_resources),
+               .resources              = msic_ocd_resources,
+       },
+};
+
+/*
+ * Other MSIC related devices which are not directly available via SFI DEVS
+ * table. These can be pseudo devices, regulators etc. which are needed for
+ * different purposes.
+ *
+ * These devices appear only after the MSIC driver itself is initialized so
+ * we can guarantee that the SCU IPC interface is ready.
+ */
+static struct mfd_cell msic_other_devs[] = {
+       /* Audio codec in the MSIC */
+       {
+               .id                     = -1,
+               .name                   = "sn95031",
+       },
+};
+
+/**
+ * intel_msic_reg_read - read a single MSIC register
+ * @reg: register to read
+ * @val: register value is placed here
+ *
+ * Read a single register from MSIC. Returns %0 on success and negative
+ * errno in case of failure.
+ *
+ * Function may sleep.
+ */
+int intel_msic_reg_read(unsigned short reg, u8 *val)
+{
+       return intel_scu_ipc_ioread8(reg, val);
+}
+EXPORT_SYMBOL_GPL(intel_msic_reg_read);
+
+/**
+ * intel_msic_reg_write - write a single MSIC register
+ * @reg: register to write
+ * @val: value to write to that register
+ *
+ * Write a single MSIC register. Returns 0 on success and negative
+ * errno in case of failure.
+ *
+ * Function may sleep.
+ */
+int intel_msic_reg_write(unsigned short reg, u8 val)
+{
+       return intel_scu_ipc_iowrite8(reg, val);
+}
+EXPORT_SYMBOL_GPL(intel_msic_reg_write);
+
+/**
+ * intel_msic_reg_update - update a single MSIC register
+ * @reg: register to update
+ * @val: value to write to the register
+ * @mask: specifies which of the bits are updated (%0 = don't update,
+ *        %1 = update)
+ *
+ * Perform an update to a register @reg. @mask is used to specify which
+ * bits are updated. Returns %0 in case of success and negative errno in
+ * case of failure.
+ *
+ * Function may sleep.
+ */
+int intel_msic_reg_update(unsigned short reg, u8 val, u8 mask)
+{
+       return intel_scu_ipc_update_register(reg, val, mask);
+}
+EXPORT_SYMBOL_GPL(intel_msic_reg_update);
+
+/**
+ * intel_msic_bulk_read - read an array of registers
+ * @reg: array of register addresses to read
+ * @buf: array where the read values are placed
+ * @count: number of registers to read
+ *
+ * Function reads @count registers from the MSIC using addresses passed in
+ * @reg. Read values are placed in @buf. Reads are performed atomically
+ * wrt. MSIC.
+ *
+ * Returns %0 in case of success and negative errno in case of failure.
+ *
+ * Function may sleep.
+ */
+int intel_msic_bulk_read(unsigned short *reg, u8 *buf, size_t count)
+{
+       if (WARN_ON(count > SCU_IPC_RWBUF_LIMIT))
+               return -EINVAL;
+
+       return intel_scu_ipc_readv(reg, buf, count);
+}
+EXPORT_SYMBOL_GPL(intel_msic_bulk_read);
+
+/**
+ * intel_msic_bulk_write - write an array of values to the MSIC registers
+ * @reg: array of registers to write
+ * @buf: values to write to each register
+ * @count: number of registers to write
+ *
+ * Function writes @count registers in @buf to MSIC. Writes are performed
+ * atomically wrt MSIC. Returns %0 in case of success and negative errno in
+ * case of failure.
+ *
+ * Function may sleep.
+ */
+int intel_msic_bulk_write(unsigned short *reg, u8 *buf, size_t count)
+{
+       if (WARN_ON(count > SCU_IPC_RWBUF_LIMIT))
+               return -EINVAL;
+
+       return intel_scu_ipc_writev(reg, buf, count);
+}
+EXPORT_SYMBOL_GPL(intel_msic_bulk_write);
+
+/**
+ * intel_msic_irq_read - read a register from an MSIC interrupt tree
+ * @msic: MSIC instance
+ * @reg: interrupt register (between %INTEL_MSIC_IRQLVL1 and
+ *      %INTEL_MSIC_RESETIRQ2)
+ * @val: value of the register is placed here
+ *
+ * This function can be used by an MSIC subdevice interrupt handler to read
+ * a register value from the MSIC interrupt tree. In this way subdevice
+ * drivers don't have to map in the interrupt tree themselves but can just
+ * call this function instead.
+ *
+ * Function doesn't sleep and is callable from interrupt context.
+ *
+ * Returns %-EINVAL if @reg is outside of the allowed register region.
+ */
+int intel_msic_irq_read(struct intel_msic *msic, unsigned short reg, u8 *val)
+{
+       if (WARN_ON(reg < INTEL_MSIC_IRQLVL1 || reg > INTEL_MSIC_RESETIRQ2))
+               return -EINVAL;
+
+       *val = readb(msic->irq_base + (reg - INTEL_MSIC_IRQLVL1));
+       return 0;
+}
+EXPORT_SYMBOL_GPL(intel_msic_irq_read);
+
+static int __devinit intel_msic_init_devices(struct intel_msic *msic)
+{
+       struct platform_device *pdev = msic->pdev;
+       struct intel_msic_platform_data *pdata = pdev->dev.platform_data;
+       int ret, i;
+
+       if (pdata->gpio) {
+               struct mfd_cell *cell = &msic_devs[INTEL_MSIC_BLOCK_GPIO];
+
+               cell->platform_data = pdata->gpio;
+               cell->pdata_size = sizeof(*pdata->gpio);
+       }
+
+       if (pdata->ocd) {
+               unsigned gpio = pdata->ocd->gpio;
+
+               ret = gpio_request_one(gpio, GPIOF_IN, "ocd_gpio");
+               if (ret) {
+                       dev_err(&pdev->dev, "failed to register OCD GPIO\n");
+                       return ret;
+               }
+
+               ret = gpio_to_irq(gpio);
+               if (ret < 0) {
+                       dev_err(&pdev->dev, "no IRQ number for OCD GPIO\n");
+                       gpio_free(gpio);
+                       return ret;
+               }
+
+               /* Update the IRQ number for the OCD */
+               pdata->irq[INTEL_MSIC_BLOCK_OCD] = ret;
+       }
+
+       for (i = 0; i < ARRAY_SIZE(msic_devs); i++) {
+               if (!pdata->irq[i])
+                       continue;
+
+               ret = mfd_add_devices(&pdev->dev, -1, &msic_devs[i], 1, NULL,
+                                     pdata->irq[i]);
+               if (ret)
+                       goto fail;
+       }
+
+       ret = mfd_add_devices(&pdev->dev, 0, msic_other_devs,
+                             ARRAY_SIZE(msic_other_devs), NULL, 0);
+       if (ret)
+               goto fail;
+
+       return 0;
+
+fail:
+       mfd_remove_devices(&pdev->dev);
+       if (pdata->ocd)
+               gpio_free(pdata->ocd->gpio);
+
+       return ret;
+}
+
+static void __devexit intel_msic_remove_devices(struct intel_msic *msic)
+{
+       struct platform_device *pdev = msic->pdev;
+       struct intel_msic_platform_data *pdata = pdev->dev.platform_data;
+
+       mfd_remove_devices(&pdev->dev);
+
+       if (pdata->ocd)
+               gpio_free(pdata->ocd->gpio);
+}
+
+static int __devinit intel_msic_probe(struct platform_device *pdev)
+{
+       struct intel_msic_platform_data *pdata = pdev->dev.platform_data;
+       struct intel_msic *msic;
+       struct resource *res;
+       u8 id0, id1;
+       int ret;
+
+       if (!pdata) {
+               dev_err(&pdev->dev, "no platform data passed\n");
+               return -EINVAL;
+       }
+
+       /* First validate that we have an MSIC in place */
+       ret = intel_scu_ipc_ioread8(INTEL_MSIC_ID0, &id0);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to identify the MSIC chip (ID0)\n");
+               return -ENXIO;
+       }
+
+       ret = intel_scu_ipc_ioread8(INTEL_MSIC_ID1, &id1);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to identify the MSIC chip (ID1)\n");
+               return -ENXIO;
+       }
+
+       if (MSIC_VENDOR(id0) != MSIC_VENDOR(id1)) {
+               dev_err(&pdev->dev, "invalid vendor ID: %x, %x\n", id0, id1);
+               return -ENXIO;
+       }
+
+       msic = kzalloc(sizeof(*msic), GFP_KERNEL);
+       if (!msic)
+               return -ENOMEM;
+
+       msic->vendor = MSIC_VENDOR(id0);
+       msic->version = MSIC_VERSION(id0);
+       msic->pdev = pdev;
+
+       /*
+        * Map in the MSIC interrupt tree area in SRAM. This is exposed to
+        * the clients via intel_msic_irq_read().
+        */
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res) {
+               dev_err(&pdev->dev, "failed to get SRAM iomem resource\n");
+               ret = -ENODEV;
+               goto fail_free_msic;
+       }
+
+       res = request_mem_region(res->start, resource_size(res), pdev->name);
+       if (!res) {
+               ret = -EBUSY;
+               goto fail_free_msic;
+       }
+
+       msic->irq_base = ioremap_nocache(res->start, resource_size(res));
+       if (!msic->irq_base) {
+               dev_err(&pdev->dev, "failed to map SRAM memory\n");
+               ret = -ENOMEM;
+               goto fail_release_region;
+       }
+
+       platform_set_drvdata(pdev, msic);
+
+       ret = intel_msic_init_devices(msic);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to initialize MSIC devices\n");
+               goto fail_unmap_mem;
+       }
+
+       dev_info(&pdev->dev, "Intel MSIC version %c%d (vendor %#x)\n",
+                MSIC_MAJOR(msic->version), MSIC_MINOR(msic->version),
+                msic->vendor);
+
+       return 0;
+
+fail_unmap_mem:
+       iounmap(msic->irq_base);
+fail_release_region:
+       release_mem_region(res->start, resource_size(res));
+fail_free_msic:
+       kfree(msic);
+
+       return ret;
+}
+
+static int __devexit intel_msic_remove(struct platform_device *pdev)
+{
+       struct intel_msic *msic = platform_get_drvdata(pdev);
+       struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+       intel_msic_remove_devices(msic);
+       platform_set_drvdata(pdev, NULL);
+       iounmap(msic->irq_base);
+       release_mem_region(res->start, resource_size(res));
+       kfree(msic);
+
+       return 0;
+}
+
+static struct platform_driver intel_msic_driver = {
+       .probe          = intel_msic_probe,
+       .remove         = __devexit_p(intel_msic_remove),
+       .driver         = {
+               .name   = "intel_msic",
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init intel_msic_init(void)
+{
+       return platform_driver_register(&intel_msic_driver);
+}
+module_init(intel_msic_init);
+
+static void __exit intel_msic_exit(void)
+{
+       platform_driver_unregister(&intel_msic_driver);
+}
+module_exit(intel_msic_exit);
+
+MODULE_DESCRIPTION("Driver for Intel MSIC");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_LICENSE("GPL");