kernel-brax3-ubuntu-touch/drivers/memory/mediatek/emi-isu.c
erascape f319b992b1 kernel-5.15: Initial import brax3 UT kernel
* halium configs enabled

Signed-off-by: erascape <erascape@proton.me>
2025-09-23 15:17:10 +00:00

277 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2019 MediaTek Inc.
*/
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <soc/mediatek/emi.h>
struct emi_isu {
unsigned int buf_size;
void __iomem *buf_addr;
void __iomem *ver_addr;
void __iomem *con_addr;
unsigned int ctrl_intf;
};
/* global pointer for sysfs operations*/
static struct emi_isu *global_emi_isu;
static ssize_t emiisu_ctrl_show(struct device_driver *driver, char *buf)
{
struct emi_isu *isu;
unsigned int state;
if (!global_emi_isu)
return 0;
isu = global_emi_isu;
if (!(isu->con_addr))
return 0;
state = readl(isu->con_addr);
return snprintf(buf, PAGE_SIZE, "isu_state: 0x%x\n", state);
}
static ssize_t emiisu_ctrl_store
(struct device_driver *driver, const char *buf, size_t count)
{
struct emi_isu *isu;
unsigned long state;
char *command;
char *backup_command;
char *ptr;
char *token[MTK_EMI_MAX_TOKEN];
int i;
if (!global_emi_isu)
return count;
isu = global_emi_isu;
if (!(isu->ctrl_intf))
return count;
if (!(isu->con_addr))
return count;
if ((strlen(buf) + 1) > MTK_EMI_MAX_CMD_LEN) {
pr_info("%s: store command overflow\n", __func__);
return count;
}
command = kmalloc((size_t)MTK_EMI_MAX_CMD_LEN, GFP_KERNEL);
if (!command)
return count;
backup_command = command;
strncpy(command, buf, (size_t)MTK_EMI_MAX_CMD_LEN);
for (i = 0; i < MTK_EMI_MAX_TOKEN; i++) {
ptr = strsep(&command, " ");
if (!ptr)
break;
token[i] = ptr;
}
if (i < 1)
goto emiisu_ctrl_store_end;
if (kstrtoul(token[0], 16, &state) == 0)
writel((unsigned int)state, isu->con_addr);
emiisu_ctrl_store_end:
kfree(backup_command);
return count;
}
static DRIVER_ATTR_RW(emiisu_ctrl);
static ssize_t read_emi_isu_buf(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buff, loff_t pos, size_t count)
{
struct emi_isu *isu;
ssize_t bytes = 0, ret;
if (!global_emi_isu)
return 0;
isu = global_emi_isu;
if (!(isu->buf_addr))
return 0;
if (!(isu->ver_addr))
return 0;
/*
* The EMI ISU buffer consists of a 4-byte header (which is stored in
* isu->ver_addr) and the content (which is stored in isu->buf_addr).
* Concatenate isu->ver_addr and isu->buf_addr and return to the reader.
*/
if (pos == 0) {
if (count < 4)
return -EINVAL;
memcpy(buff, isu->ver_addr, 4);
bytes += 4;
buff += 4;
count -= 4;
pos += 4;
}
pos -= 4;
ret = memory_read_from_buffer(buff, count, &pos,
isu->buf_addr, isu->buf_size);
if (ret < 0)
return ret;
else
return bytes + ret;
}
static struct bin_attribute emi_isu_buf_attr = {
.attr = {.name = "emi_isu_buf", .mode = 0444},
.read = read_emi_isu_buf,
};
static const struct of_device_id emiisu_of_ids[] = {
{.compatible = "mediatek,common-emiisu",},
{}
};
static int emiisu_probe(struct platform_device *pdev)
{
struct device_node *emiisu_node = pdev->dev.of_node;
struct emi_isu *isu;
unsigned long long addr_temp;
int ret;
dev_info(&pdev->dev, "driver probed\n");
isu = devm_kzalloc(&pdev->dev,
sizeof(struct emi_isu), GFP_KERNEL);
if (!isu)
return -ENOMEM;
ret = of_property_read_u32(emiisu_node,
"buf_size", &(isu->buf_size));
if (ret) {
dev_err(&pdev->dev, "No buf_size\n");
return -EINVAL;
}
ret = of_property_read_u64(emiisu_node, "buf_addr", &addr_temp);
if (ret) {
dev_err(&pdev->dev, "No buf_addr\n");
return -EINVAL;
}
if (addr_temp)
isu->buf_addr = ioremap_wc(
(phys_addr_t)addr_temp, isu->buf_size);
else
isu->buf_addr = NULL;
ret = of_property_read_u64(emiisu_node, "ver_addr", &addr_temp);
if (ret) {
dev_err(&pdev->dev, "No ver_addr\n");
return -EINVAL;
}
if (addr_temp)
isu->ver_addr = ioremap((phys_addr_t)addr_temp, 4);
else
isu->ver_addr = NULL;
ret = of_property_read_u64(emiisu_node, "con_addr", &addr_temp);
if (ret) {
dev_err(&pdev->dev, "No con_addr\n");
return -EINVAL;
}
if (addr_temp)
isu->con_addr = ioremap((phys_addr_t)addr_temp, 4);
else
isu->con_addr = NULL;
ret = of_property_read_u32(emiisu_node,
"ctrl_intf", &(isu->ctrl_intf));
if (ret) {
dev_err(&pdev->dev, "No ctrl_intf\n");
return -EINVAL;
}
/* max buffer size = ISU buffer size + 4 bytes of version header */
emi_isu_buf_attr.size = isu->buf_size + 4;
ret = sysfs_create_bin_file(&pdev->dev.kobj, &emi_isu_buf_attr);
if (ret) {
dev_err(&pdev->dev, "Failed to create buf file\n");
return ret;
}
platform_set_drvdata(pdev, isu);
global_emi_isu = isu;
dev_info(&pdev->dev, "%s(%x),%s(%lx),%s(%lx),%s(%lx),%s(%d)\n",
"buf_size", isu->buf_size,
"buf_addr", (unsigned long)(isu->buf_addr),
"ver_addr", (unsigned long)(isu->ver_addr),
"con_addr", (unsigned long)(isu->con_addr),
"ctrl_intf", isu->ctrl_intf);
return 0;
}
static int emiisu_remove(struct platform_device *pdev)
{
sysfs_remove_bin_file(&pdev->dev.kobj, &emi_isu_buf_attr);
global_emi_isu = NULL;
return 0;
}
static struct platform_driver emiisu_drv = {
.probe = emiisu_probe,
.remove = emiisu_remove,
.driver = {
.name = "emiisu_drv",
.owner = THIS_MODULE,
.of_match_table = emiisu_of_ids,
},
};
int emiisu_init(void)
{
int ret;
pr_info("emiisu wad loaded\n");
ret = platform_driver_register(&emiisu_drv);
if (ret) {
pr_err("emiisu: failed to register dirver\n");
return ret;
}
ret = driver_create_file(&emiisu_drv.driver,
&driver_attr_emiisu_ctrl);
if (ret) {
pr_err("emiisu: failed to create control file\n");
return ret;
}
return 0;
}
MODULE_DESCRIPTION("MediaTek EMI Driver");
MODULE_LICENSE("GPL v2");