cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i2c.c (3956B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Helper module for board specific I2C bus registration
      4 *
      5 * Copyright (C) 2009 Nokia Corporation.
      6 */
      7
      8#include <linux/i2c.h>
      9#include <linux/platform_data/i2c-omap.h>
     10
     11#include "mux.h"
     12#include "soc.h"
     13#include "i2c.h"
     14
     15#define OMAP_I2C_SIZE		0x3f
     16#define OMAP1_I2C_BASE		0xfffb3800
     17
     18static const char name[] = "omap_i2c";
     19
     20static struct resource i2c_resources[2] = {
     21};
     22
     23static struct platform_device omap_i2c_devices[1] = {
     24};
     25
     26static void __init omap1_i2c_mux_pins(int bus_id)
     27{
     28	if (cpu_is_omap7xx()) {
     29		omap_cfg_reg(I2C_7XX_SDA);
     30		omap_cfg_reg(I2C_7XX_SCL);
     31	} else {
     32		omap_cfg_reg(I2C_SDA);
     33		omap_cfg_reg(I2C_SCL);
     34	}
     35}
     36
     37int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *pdata,
     38				int bus_id)
     39{
     40	struct platform_device *pdev;
     41	struct resource *res;
     42
     43	if (bus_id > 1)
     44		return -EINVAL;
     45
     46	omap1_i2c_mux_pins(bus_id);
     47
     48	pdev = &omap_i2c_devices[bus_id - 1];
     49	pdev->id = bus_id;
     50	pdev->name = name;
     51	pdev->num_resources = ARRAY_SIZE(i2c_resources);
     52	res = i2c_resources;
     53	res[0].start = OMAP1_I2C_BASE;
     54	res[0].end = res[0].start + OMAP_I2C_SIZE;
     55	res[0].flags = IORESOURCE_MEM;
     56	res[1].start = INT_I2C;
     57	res[1].flags = IORESOURCE_IRQ;
     58	pdev->resource = res;
     59
     60	/* all OMAP1 have IP version 1 register set */
     61	pdata->rev = OMAP_I2C_IP_VERSION_1;
     62
     63	/* all OMAP1 I2C are implemented like this */
     64	pdata->flags = OMAP_I2C_FLAG_NO_FIFO |
     65		       OMAP_I2C_FLAG_SIMPLE_CLOCK |
     66		       OMAP_I2C_FLAG_16BIT_DATA_REG |
     67		       OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK;
     68
     69	/* how the cpu bus is wired up differs for 7xx only */
     70
     71	if (cpu_is_omap7xx())
     72		pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_1;
     73	else
     74		pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_2;
     75
     76	pdev->dev.platform_data = pdata;
     77
     78	return platform_device_register(pdev);
     79}
     80
     81#define OMAP_I2C_MAX_CONTROLLERS 4
     82static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS];
     83
     84#define OMAP_I2C_CMDLINE_SETUP	(BIT(31))
     85
     86/**
     87 * omap_i2c_bus_setup - Process command line options for the I2C bus speed
     88 * @str: String of options
     89 *
     90 * This function allow to override the default I2C bus speed for given I2C
     91 * bus with a command line option.
     92 *
     93 * Format: i2c_bus=bus_id,clkrate (in kHz)
     94 *
     95 * Returns 1 on success, 0 otherwise.
     96 */
     97static int __init omap_i2c_bus_setup(char *str)
     98{
     99	int ints[3];
    100
    101	get_options(str, 3, ints);
    102	if (ints[0] < 2 || ints[1] < 1 ||
    103			ints[1] > OMAP_I2C_MAX_CONTROLLERS)
    104		return 0;
    105	i2c_pdata[ints[1] - 1].clkrate = ints[2];
    106	i2c_pdata[ints[1] - 1].clkrate |= OMAP_I2C_CMDLINE_SETUP;
    107
    108	return 1;
    109}
    110__setup("i2c_bus=", omap_i2c_bus_setup);
    111
    112/*
    113 * Register busses defined in command line but that are not registered with
    114 * omap_register_i2c_bus from board initialization code.
    115 */
    116int __init omap_register_i2c_bus_cmdline(void)
    117{
    118	int i, err = 0;
    119
    120	for (i = 0; i < ARRAY_SIZE(i2c_pdata); i++)
    121		if (i2c_pdata[i].clkrate & OMAP_I2C_CMDLINE_SETUP) {
    122			i2c_pdata[i].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
    123			err = omap_i2c_add_bus(&i2c_pdata[i], i + 1);
    124			if (err)
    125				goto out;
    126		}
    127
    128out:
    129	return err;
    130}
    131
    132/**
    133 * omap_register_i2c_bus - register I2C bus with device descriptors
    134 * @bus_id: bus id counting from number 1
    135 * @clkrate: clock rate of the bus in kHz
    136 * @info: pointer into I2C device descriptor table or NULL
    137 * @len: number of descriptors in the table
    138 *
    139 * Returns 0 on success or an error code.
    140 */
    141int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
    142			  struct i2c_board_info const *info,
    143			  unsigned len)
    144{
    145	int err;
    146
    147	BUG_ON(bus_id < 1 || bus_id > OMAP_I2C_MAX_CONTROLLERS);
    148
    149	if (info) {
    150		err = i2c_register_board_info(bus_id, info, len);
    151		if (err)
    152			return err;
    153	}
    154
    155	if (!i2c_pdata[bus_id - 1].clkrate)
    156		i2c_pdata[bus_id - 1].clkrate = clkrate;
    157
    158	i2c_pdata[bus_id - 1].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
    159
    160	return omap_i2c_add_bus(&i2c_pdata[bus_id - 1], bus_id);
    161}
    162
    163static  int __init omap_i2c_cmdline(void)
    164{
    165	return omap_register_i2c_bus_cmdline();
    166}
    167subsys_initcall(omap_i2c_cmdline);