diff options
Diffstat (limited to 'kernel/drivers/mfd/intel_msic.c')
| -rw-r--r-- | kernel/drivers/mfd/intel_msic.c | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/kernel/drivers/mfd/intel_msic.c b/kernel/drivers/mfd/intel_msic.c new file mode 100644 index 000000000..25d486c54 --- /dev/null +++ b/kernel/drivers/mfd/intel_msic.c @@ -0,0 +1,457 @@ +/* + * 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 subtract 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 const 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 = dev_get_platdata(&pdev->dev); + 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 = devm_gpio_request_one(&pdev->dev, 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"); + 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); + + return ret; +} + +static void intel_msic_remove_devices(struct intel_msic *msic) +{ + struct platform_device *pdev = msic->pdev; + + mfd_remove_devices(&pdev->dev); +} + +static int intel_msic_probe(struct platform_device *pdev) +{ + struct intel_msic_platform_data *pdata = dev_get_platdata(&pdev->dev); + 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); + 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); + + return 0; +} + +static struct platform_driver intel_msic_driver = { + .probe = intel_msic_probe, + .remove = intel_msic_remove, + .driver = { + .name = "intel_msic", + }, +}; + +module_platform_driver(intel_msic_driver); + +MODULE_DESCRIPTION("Driver for Intel MSIC"); +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>"); +MODULE_LICENSE("GPL"); |