cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

htc-pasic3.c (4987B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Core driver for HTC PASIC3 LED/DS1WM chip.
      4 *
      5 * Copyright (C) 2006 Philipp Zabel <philipp.zabel@gmail.com>
      6 */
      7
      8#include <linux/init.h>
      9#include <linux/module.h>
     10#include <linux/platform_device.h>
     11
     12#include <linux/gpio.h>
     13#include <linux/io.h>
     14#include <linux/irq.h>
     15#include <linux/interrupt.h>
     16#include <linux/mfd/core.h>
     17#include <linux/mfd/ds1wm.h>
     18#include <linux/mfd/htc-pasic3.h>
     19#include <linux/slab.h>
     20
     21struct pasic3_data {
     22	void __iomem *mapping;
     23	unsigned int bus_shift;
     24};
     25
     26#define REG_ADDR  5
     27#define REG_DATA  6
     28
     29#define READ_MODE 0x80
     30
     31/*
     32 * write to a secondary register on the PASIC3
     33 */
     34void pasic3_write_register(struct device *dev, u32 reg, u8 val)
     35{
     36	struct pasic3_data *asic = dev_get_drvdata(dev);
     37	int bus_shift = asic->bus_shift;
     38	void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
     39	void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
     40
     41	__raw_writeb(~READ_MODE & reg, addr);
     42	__raw_writeb(val, data);
     43}
     44EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
     45
     46/*
     47 * read from a secondary register on the PASIC3
     48 */
     49u8 pasic3_read_register(struct device *dev, u32 reg)
     50{
     51	struct pasic3_data *asic = dev_get_drvdata(dev);
     52	int bus_shift = asic->bus_shift;
     53	void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
     54	void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
     55
     56	__raw_writeb(READ_MODE | reg, addr);
     57	return __raw_readb(data);
     58}
     59EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
     60
     61/*
     62 * LEDs
     63 */
     64
     65static struct mfd_cell led_cell __initdata = {
     66	.name = "leds-pasic3",
     67};
     68
     69/*
     70 * DS1WM
     71 */
     72
     73static int ds1wm_enable(struct platform_device *pdev)
     74{
     75	struct device *dev = pdev->dev.parent;
     76	int c;
     77
     78	c = pasic3_read_register(dev, 0x28);
     79	pasic3_write_register(dev, 0x28, c & 0x7f);
     80
     81	dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
     82	return 0;
     83}
     84
     85static int ds1wm_disable(struct platform_device *pdev)
     86{
     87	struct device *dev = pdev->dev.parent;
     88	int c;
     89
     90	c = pasic3_read_register(dev, 0x28);
     91	pasic3_write_register(dev, 0x28, c | 0x80);
     92
     93	dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
     94	return 0;
     95}
     96
     97static struct ds1wm_driver_data ds1wm_pdata = {
     98	.active_high = 0,
     99	.reset_recover_delay = 1,
    100};
    101
    102static struct resource ds1wm_resources[] __initdata = {
    103	[0] = {
    104		.start  = 0,
    105		.flags  = IORESOURCE_MEM,
    106	},
    107	[1] = {
    108		.start  = 0,
    109		.end    = 0,
    110		.flags  = IORESOURCE_IRQ,
    111	},
    112};
    113
    114static const struct mfd_cell ds1wm_cell __initconst = {
    115	.name          = "ds1wm",
    116	.enable        = ds1wm_enable,
    117	.disable       = ds1wm_disable,
    118	.platform_data = &ds1wm_pdata,
    119	.pdata_size    = sizeof(ds1wm_pdata),
    120	.num_resources = 2,
    121	.resources     = ds1wm_resources,
    122};
    123
    124static int __init pasic3_probe(struct platform_device *pdev)
    125{
    126	struct pasic3_platform_data *pdata = dev_get_platdata(&pdev->dev);
    127	struct device *dev = &pdev->dev;
    128	struct pasic3_data *asic;
    129	struct resource *r;
    130	int ret;
    131	int irq = 0;
    132
    133	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
    134	if (r) {
    135		ds1wm_resources[1].flags = IORESOURCE_IRQ | (r->flags &
    136			(IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE));
    137		irq = r->start;
    138	}
    139
    140	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    141	if (!r)
    142		return -ENXIO;
    143
    144	if (!request_mem_region(r->start, resource_size(r), "pasic3"))
    145		return -EBUSY;
    146
    147	asic = devm_kzalloc(dev, sizeof(struct pasic3_data), GFP_KERNEL);
    148	if (!asic)
    149		return -ENOMEM;
    150
    151	platform_set_drvdata(pdev, asic);
    152
    153	asic->mapping = ioremap(r->start, resource_size(r));
    154	if (!asic->mapping) {
    155		dev_err(dev, "couldn't ioremap PASIC3\n");
    156		return -ENOMEM;
    157	}
    158
    159	/* calculate bus shift from mem resource */
    160	asic->bus_shift = (resource_size(r) - 5) >> 3;
    161
    162	if (pdata && pdata->clock_rate) {
    163		ds1wm_pdata.clock_rate = pdata->clock_rate;
    164		/* the first 5 PASIC3 registers control the DS1WM */
    165		ds1wm_resources[0].end = (5 << asic->bus_shift) - 1;
    166		ret = mfd_add_devices(&pdev->dev, pdev->id,
    167				      &ds1wm_cell, 1, r, irq, NULL);
    168		if (ret < 0)
    169			dev_warn(dev, "failed to register DS1WM\n");
    170	}
    171
    172	if (pdata && pdata->led_pdata) {
    173		led_cell.platform_data = pdata->led_pdata;
    174		led_cell.pdata_size = sizeof(struct pasic3_leds_machinfo);
    175		ret = mfd_add_devices(&pdev->dev, pdev->id, &led_cell, 1, r,
    176				      0, NULL);
    177		if (ret < 0)
    178			dev_warn(dev, "failed to register LED device\n");
    179	}
    180
    181	return 0;
    182}
    183
    184static int pasic3_remove(struct platform_device *pdev)
    185{
    186	struct pasic3_data *asic = platform_get_drvdata(pdev);
    187	struct resource *r;
    188
    189	mfd_remove_devices(&pdev->dev);
    190
    191	iounmap(asic->mapping);
    192	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    193	release_mem_region(r->start, resource_size(r));
    194	return 0;
    195}
    196
    197MODULE_ALIAS("platform:pasic3");
    198
    199static struct platform_driver pasic3_driver = {
    200	.driver		= {
    201		.name	= "pasic3",
    202	},
    203	.remove		= pasic3_remove,
    204};
    205
    206module_platform_driver_probe(pasic3_driver, pasic3_probe);
    207
    208MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
    209MODULE_DESCRIPTION("Core driver for HTC PASIC3");
    210MODULE_LICENSE("GPL");