/*
* 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/err.h>
#include <linux/gpio.h>
#include <linux/io.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 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], NULL);
if (ret)
goto fail;
}
ret = mfd_add_devices(&pdev->dev, 0, msic_other_devs,
ARRAY_SIZE(msic_other_devs), NULL, 0, NULL);
if (ret)
goto fail;
return 0;
fail:
mfd_remove_devices(&pdev->dev);
if (pdata->ocd)
gpio_free(pdata->ocd->gpio);
return ret;
}
static void 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 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 = devm_kzalloc(&pdev->dev, 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");
return -ENODEV;
}
msic->irq_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(msic->irq_base))
return PTR_ERR(msic->irq_base);
platform_set_drvdata(pdev, msic);
ret = intel_msic_init_devices(msic);
if (ret) {
dev_err(&pdev->dev, "failed to initialize MSIC devices\n");
return ret;
}
dev_info(&pdev->dev, "Intel MSIC version %c%d (vendor %#x)\n",
MSIC_MAJOR(msic->version), MSIC_MINOR(msic->version),
msic->vendor);
return 0;
}
static int intel_msic_remove(struct platform_device *pdev)
{
struct intel_msic *msic = platform_get_drvdata(pdev);
intel_msic_remove_devices(msic);
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver intel_msic_driver = {
.probe = intel_msic_probe,
.remove = intel_msic_remove,
.driver = {
.name = "intel_msic",
.owner = THIS_MODULE,
},
};
module_platform_driver(intel_msic_driver);
MODULE_DESCRIPTION("Driver for Intel MSIC");
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
MODULE_LICENSE("GPL");
