linux-zen-server/arch/sh/drivers/platform_early.c

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2023-08-30 17:53:23 +02:00
// SPDX--License-Identifier: GPL-2.0
#include <asm/platform_early.h>
#include <linux/mod_devicetable.h>
#include <linux/pm.h>
static __initdata LIST_HEAD(sh_early_platform_driver_list);
static __initdata LIST_HEAD(sh_early_platform_device_list);
static const struct platform_device_id *
platform_match_id(const struct platform_device_id *id,
struct platform_device *pdev)
{
while (id->name[0]) {
if (strcmp(pdev->name, id->name) == 0) {
pdev->id_entry = id;
return id;
}
id++;
}
return NULL;
}
static int platform_match(struct device *dev, struct device_driver *drv)
{
struct platform_device *pdev = to_platform_device(dev);
struct platform_driver *pdrv = to_platform_driver(drv);
/* When driver_override is set, only bind to the matching driver */
if (pdev->driver_override)
return !strcmp(pdev->driver_override, drv->name);
/* Then try to match against the id table */
if (pdrv->id_table)
return platform_match_id(pdrv->id_table, pdev) != NULL;
/* fall-back to driver name match */
return (strcmp(pdev->name, drv->name) == 0);
}
#ifdef CONFIG_PM
static void device_pm_init_common(struct device *dev)
{
if (!dev->power.early_init) {
spin_lock_init(&dev->power.lock);
dev->power.qos = NULL;
dev->power.early_init = true;
}
}
static void pm_runtime_early_init(struct device *dev)
{
dev->power.disable_depth = 1;
device_pm_init_common(dev);
}
#else
static void pm_runtime_early_init(struct device *dev) {}
#endif
/**
* sh_early_platform_driver_register - register early platform driver
* @epdrv: sh_early_platform driver structure
* @buf: string passed from early_param()
*
* Helper function for sh_early_platform_init() / sh_early_platform_init_buffer()
*/
int __init sh_early_platform_driver_register(struct sh_early_platform_driver *epdrv,
char *buf)
{
char *tmp;
int n;
/* Simply add the driver to the end of the global list.
* Drivers will by default be put on the list in compiled-in order.
*/
if (!epdrv->list.next) {
INIT_LIST_HEAD(&epdrv->list);
list_add_tail(&epdrv->list, &sh_early_platform_driver_list);
}
/* If the user has specified device then make sure the driver
* gets prioritized. The driver of the last device specified on
* command line will be put first on the list.
*/
n = strlen(epdrv->pdrv->driver.name);
if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) {
list_move(&epdrv->list, &sh_early_platform_driver_list);
/* Allow passing parameters after device name */
if (buf[n] == '\0' || buf[n] == ',')
epdrv->requested_id = -1;
else {
epdrv->requested_id = simple_strtoul(&buf[n + 1],
&tmp, 10);
if (buf[n] != '.' || (tmp == &buf[n + 1])) {
epdrv->requested_id = EARLY_PLATFORM_ID_ERROR;
n = 0;
} else
n += strcspn(&buf[n + 1], ",") + 1;
}
if (buf[n] == ',')
n++;
if (epdrv->bufsize) {
memcpy(epdrv->buffer, &buf[n],
min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1));
epdrv->buffer[epdrv->bufsize - 1] = '\0';
}
}
return 0;
}
/**
* sh_early_platform_add_devices - adds a number of early platform devices
* @devs: array of early platform devices to add
* @num: number of early platform devices in array
*
* Used by early architecture code to register early platform devices and
* their platform data.
*/
void __init sh_early_platform_add_devices(struct platform_device **devs, int num)
{
struct device *dev;
int i;
/* simply add the devices to list */
for (i = 0; i < num; i++) {
dev = &devs[i]->dev;
if (!dev->devres_head.next) {
pm_runtime_early_init(dev);
INIT_LIST_HEAD(&dev->devres_head);
list_add_tail(&dev->devres_head,
&sh_early_platform_device_list);
}
}
}
/**
* sh_early_platform_driver_register_all - register early platform drivers
* @class_str: string to identify early platform driver class
*
* Used by architecture code to register all early platform drivers
* for a certain class. If omitted then only early platform drivers
* with matching kernel command line class parameters will be registered.
*/
void __init sh_early_platform_driver_register_all(char *class_str)
{
/* The "class_str" parameter may or may not be present on the kernel
* command line. If it is present then there may be more than one
* matching parameter.
*
* Since we register our early platform drivers using early_param()
* we need to make sure that they also get registered in the case
* when the parameter is missing from the kernel command line.
*
* We use parse_early_options() to make sure the early_param() gets
* called at least once. The early_param() may be called more than
* once since the name of the preferred device may be specified on
* the kernel command line. sh_early_platform_driver_register() handles
* this case for us.
*/
parse_early_options(class_str);
}
/**
* sh_early_platform_match - find early platform device matching driver
* @epdrv: early platform driver structure
* @id: id to match against
*/
static struct platform_device * __init
sh_early_platform_match(struct sh_early_platform_driver *epdrv, int id)
{
struct platform_device *pd;
list_for_each_entry(pd, &sh_early_platform_device_list, dev.devres_head)
if (platform_match(&pd->dev, &epdrv->pdrv->driver))
if (pd->id == id)
return pd;
return NULL;
}
/**
* sh_early_platform_left - check if early platform driver has matching devices
* @epdrv: early platform driver structure
* @id: return true if id or above exists
*/
static int __init sh_early_platform_left(struct sh_early_platform_driver *epdrv,
int id)
{
struct platform_device *pd;
list_for_each_entry(pd, &sh_early_platform_device_list, dev.devres_head)
if (platform_match(&pd->dev, &epdrv->pdrv->driver))
if (pd->id >= id)
return 1;
return 0;
}
/**
* sh_early_platform_driver_probe_id - probe drivers matching class_str and id
* @class_str: string to identify early platform driver class
* @id: id to match against
* @nr_probe: number of platform devices to successfully probe before exiting
*/
static int __init sh_early_platform_driver_probe_id(char *class_str,
int id,
int nr_probe)
{
struct sh_early_platform_driver *epdrv;
struct platform_device *match;
int match_id;
int n = 0;
int left = 0;
list_for_each_entry(epdrv, &sh_early_platform_driver_list, list) {
/* only use drivers matching our class_str */
if (strcmp(class_str, epdrv->class_str))
continue;
if (id == -2) {
match_id = epdrv->requested_id;
left = 1;
} else {
match_id = id;
left += sh_early_platform_left(epdrv, id);
/* skip requested id */
switch (epdrv->requested_id) {
case EARLY_PLATFORM_ID_ERROR:
case EARLY_PLATFORM_ID_UNSET:
break;
default:
if (epdrv->requested_id == id)
match_id = EARLY_PLATFORM_ID_UNSET;
}
}
switch (match_id) {
case EARLY_PLATFORM_ID_ERROR:
pr_warn("%s: unable to parse %s parameter\n",
class_str, epdrv->pdrv->driver.name);
fallthrough;
case EARLY_PLATFORM_ID_UNSET:
match = NULL;
break;
default:
match = sh_early_platform_match(epdrv, match_id);
}
if (match) {
/*
* Set up a sensible init_name to enable
* dev_name() and others to be used before the
* rest of the driver core is initialized.
*/
if (!match->dev.init_name && slab_is_available()) {
if (match->id != -1)
match->dev.init_name =
kasprintf(GFP_KERNEL, "%s.%d",
match->name,
match->id);
else
match->dev.init_name =
kasprintf(GFP_KERNEL, "%s",
match->name);
if (!match->dev.init_name)
return -ENOMEM;
}
if (epdrv->pdrv->probe(match))
pr_warn("%s: unable to probe %s early.\n",
class_str, match->name);
else
n++;
}
if (n >= nr_probe)
break;
}
if (left)
return n;
else
return -ENODEV;
}
/**
* sh_early_platform_driver_probe - probe a class of registered drivers
* @class_str: string to identify early platform driver class
* @nr_probe: number of platform devices to successfully probe before exiting
* @user_only: only probe user specified early platform devices
*
* Used by architecture code to probe registered early platform drivers
* within a certain class. For probe to happen a registered early platform
* device matching a registered early platform driver is needed.
*/
int __init sh_early_platform_driver_probe(char *class_str,
int nr_probe,
int user_only)
{
int k, n, i;
n = 0;
for (i = -2; n < nr_probe; i++) {
k = sh_early_platform_driver_probe_id(class_str, i, nr_probe - n);
if (k < 0)
break;
n += k;
if (user_only)
break;
}
return n;
}
/**
* early_platform_cleanup - clean up early platform code
*/
void __init early_platform_cleanup(void)
{
struct platform_device *pd, *pd2;
/* clean up the devres list used to chain devices */
list_for_each_entry_safe(pd, pd2, &sh_early_platform_device_list,
dev.devres_head) {
list_del(&pd->dev.devres_head);
memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
}
}