s3c2410 usb主机驱动解析ohci-s3c2410.c
以下是平台设备源码
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/platform_device.h>
#include <mach/irqs.h>
#include <mach/map.h>
#include <plat/devs.h>
#include <plat/usb-control.h>
/*usb地址和中断资源
static struct resource s3c_usb_resource[] = {
[0] = {
.start = S3C_PA_USBHOST, //基址开始地址
.end = S3C_PA_USBHOST + 0x100 - 1,//基址结束地址
.flags = IORESOURCE_MEM,//资源内存
},
[1] = {
.start = IRQ_USBH,
.end = IRQ_USBH,//中断地址
.flags = IORESOURCE_IRQ,
}
};
static u64 s3c_device_usb_dmamask = 0xffffffffUL;//指明掩码
/*填充ohci平台设备*/
struct platform_device s3c_device_ohci = {
.name = "s3c2410-ohci",
.id = -1,
.num_resources = ARRAY_SIZE(s3c_usb_resource),
.resource = s3c_usb_resource,
.dev = {
.dma_mask = &s3c_device_usb_dmamask,
.coherent_dma_mask = 0xffffffffUL
}
};
EXPORT_SYMBOL(s3c_device_ohci);
/*建立平台数据，在后面的主机驱动程序中会被调用*/
void __init s3c_ohci_set_platdata(struct s3c2410_hcd_info *info)
{
struct s3c2410_hcd_info *npd;
npd = kmemdup(info, sizeof(struct s3c2410_hcd_info), GFP_KERNEL);
if (!npd)
printk(KERN_ERR "%s: no memory for platform data/n", __func__);
s3c_device_ohci.dev.platform_data = npd；//刚申请的内存保存到平台设备数据中
}
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <plat/usb-control.h>
/*指定2个端口*/
#define valid_port(idx) ((idx) == 1 || (idx) == 2)
/* 时钟与hcd发生联系 */
static struct clk *clk;
static struct clk *usb_clk;
static void s3c2410_hcd_oc(struct s3c2410_hcd_info *info, int port_oc);
static struct s3c2410_hcd_info *to_s3c2410_info(struct usb_hcd *hcd)
{
return hcd->self.controller->platform_data;
}
/*传输函数*/
static void s3c2410_start_hc(struct platform_device *dev, struct usb_hcd *hcd)
{
struct s3c2410_hcd_info *info = dev->dev.platform_data;//得到平台数据
dev_dbg(&dev->dev, "s3c2410_start_hc:/n");//打印消息
clk_enable(usb_clk);//使能总线时钟
mdelay(2); /* let the bus clock stabilise */
clk_enable(clk);//使能时钟
if (info != NULL) {
info->hcd = hcd;
info->report_oc = s3c2410_hcd_oc;填充s3c2410_hcd_info中
if (info->enable_oc != NULL) {
(info->enable_oc)(info, 1);
}
}
}
static void s3c2410_stop_hc(struct platform_device *dev)
{
struct s3c2410_hcd_info *info = dev->dev.platform_data;
dev_dbg(&dev->dev, "s3c2410_stop_hc:/n");
if (info != NULL) {
info->report_oc = NULL;
info->hcd = NULL;
if (info->enable_oc != NULL) {
(info->enable_oc)(info, 0);
}
}
clk_disable(clk);
clk_disable(usb_clk);
}
/* ohci_s3c2410_hub_status_data
*
更新hub状态
*/
static int
ohci_s3c2410_hub_status_data (struct usb_hcd *hcd, char *buf)
{
struct s3c2410_hcd_info *info = to_s3c2410_info(hcd);
struct s3c2410_hcd_port *port;
int orig;
int portno;
orig = ohci_hub_status_data (hcd, buf);
if (info == NULL)
return orig;
port = &info->port[0];
/* mark any changed port as changed */
for (portno = 0; portno < 2; port++, portno++) {
if (port->oc_changed == 1 &&
port->flags & S3C_HCDFLG_USED) {
dev_dbg(hcd->self.controller,
"oc change on port %d/n", portno);
if (orig < 1)
orig = 1;
buf[0] |= 1<<(portno+1);
}
}
return orig;
}
/* s3c2410_usb_set_power
*
*配置端口电源
*/
static void s3c2410_usb_set_power(struct s3c2410_hcd_info *info,
int port, int to)
{
if (info == NULL)
return;
if (info->power_control != NULL) {
info->port[port-1].power = to;
(info->power_control)(port-1, to);
}
}
/* ohci_s3c2410_hub_control
*
* look at control requests to the hub, and see if we need
* to take any action or over-ride the results from the
* request.
*/
static int ohci_s3c2410_hub_control (
struct usb_hcd *hcd,
u16 typeReq,
u16 wValue,
u16 wIndex,
char *buf,
u16 wLength)
{
struct s3c2410_hcd_info *info = to_s3c2410_info(hcd);
struct usb_hub_descriptor *desc;
int ret = -EINVAL;
u32 *data = (u32 *)buf;
dev_dbg(hcd->self.controller,
"s3c2410_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)/n",
hcd, typeReq, wValue, wIndex, buf, wLength);
/* if we are only an humble host without any special capabilities
* process the request straight away and exit */
if (info == NULL) {
ret = ohci_hub_control(hcd, typeReq, wValue,
wIndex, buf, wLength);
goto out;
}
/* check the request to see if it needs handling */
switch (typeReq) {
case SetPortFeature:
if (wValue == USB_PORT_FEAT_POWER) {
dev_dbg(hcd->self.controller, "SetPortFeat: POWER/n");
s3c2410_usb_set_power(info, wIndex, 1);
goto out;
}
break;
case ClearPortFeature:
switch (wValue) {
case USB_PORT_FEAT_C_OVER_CURRENT:
dev_dbg(hcd->self.controller,
"ClearPortFeature: C_OVER_CURRENT/n");
if (valid_port(wIndex)) {
info->port[wIndex-1].oc_changed = 0;
info->port[wIndex-1].oc_status = 0;
}
goto out;
case USB_PORT_FEAT_OVER_CURRENT:
dev_dbg(hcd->self.controller,
"ClearPortFeature: OVER_CURRENT/n");
if (valid_port(wIndex)) {
info->port[wIndex-1].oc_status = 0;
}
goto out;
case USB_PORT_FEAT_POWER:
dev_dbg(hcd->self.controller,
"ClearPortFeature: POWER/n");
if (valid_port(wIndex)) {
s3c2410_usb_set_power(info, wIndex, 0);
return 0;
}
}
break;
}
ret = ohci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
if (ret)
goto out;
switch (typeReq) {
case GetHubDescriptor:
/* update the hub's descriptor */
desc = (struct usb_hub_descriptor *)buf;
if (info->power_control == NULL)
return ret;
dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x/n",
desc->wHubCharacteristics);
/* remove the old configurations for power-switching, and
* over-current protection, and insert our new configuration
*/
desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
desc->wHubCharacteristics |= cpu_to_le16(0x0001);
if (info->enable_oc) {
desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
desc->wHubCharacteristics |= cpu_to_le16(0x0008|0x0001);
}
dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x/n",
desc->wHubCharacteristics);
return ret;
case GetPortStatus:
/* check port status */
dev_dbg(hcd->self.controller, "GetPortStatus(%d)/n", wIndex);
if (valid_port(wIndex)) {
if (info->port[wIndex-1].oc_changed) {
*data |= cpu_to_le32(RH_PS_OCIC);
}
if (info->port[wIndex-1].oc_status) {
*data |= cpu_to_le32(RH_PS_POCI);
}
}
}
out:
return ret;
}
/* s3c2410_hcd_oc
*
* handle an over-current report
*/
static void s3c2410_hcd_oc(struct s3c2410_hcd_info *info, int port_oc)
{
struct s3c2410_hcd_port *port;
struct usb_hcd *hcd;
unsigned long flags;
int portno;
if (info == NULL)
return;
port = &info->port[0];
hcd = info->hcd;
local_irq_save(flags);
for (portno = 0; portno < 2; port++, portno++) {
if (port_oc & (1<<portno) &&
port->flags & S3C_HCDFLG_USED) {
port->oc_status = 1;
port->oc_changed = 1;
/* ok, once over-current is detected,
the port needs to be powered down */
s3c2410_usb_set_power(info, portno+1, 0);
}
}
local_irq_restore(flags);
}
/* may be called without controller electrically present */
/* may be called with controller, bus, and devices active */
/*
* usb_hcd_s3c2410_remove - shutdown processing for HCD
* @dev: USB Host Controller being removed
* Context: !in_interrupt()
*
* Reverses the effect of usb_hcd_3c2410_probe(), first invoking
* the HCD's stop() method. It is always called from a thread
* context, normally "rmmod", "apmd", or something similar.
*
*/
static void
usb_hcd_s3c2410_remove (struct usb_hcd *hcd, struct platform_device *dev)
{
usb_remove_hcd(hcd);
s3c2410_stop_hc(dev);
iounmap(hcd->regs);
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
usb_put_hcd(hcd);
}
/*使能时钟，寄存器映射
*/
static int usb_hcd_s3c2410_probe (const struct hc_driver *driver,
struct platform_device *dev)
{
struct usb_hcd *hcd = NULL;
int retval;
s3c2410_usb_set_power(dev->dev.platform_data, 1, 1);
s3c2410_usb_set_power(dev->dev.platform_data, 2, 1);
hcd = usb_create_hcd(driver, &dev->dev, "s3c24xx");//申请建立hcd
if (hcd == NULL)
return -ENOMEM;
hcd->rsrc_start = dev->resource[0].start;//hcd基址内存地址的开始
hcd->rsrc_len = dev->resource[0].end - dev->resource[0].start + 1;基址内存地址长度
if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
dev_err(&dev->dev, "request_mem_region failed/n");
retval = -EBUSY;
goto err_put;
}//如果刚才指定的I/O内存申请失败则dev_err
clk = clk_get(&dev->dev, "usb-host");//使能时钟
if (IS_ERR(clk)) {
dev_err(&dev->dev, "cannot get usb-host clock/n");
retval = -ENOENT;
goto err_mem;
}
usb_clk = clk_get(&dev->dev, "usb-bus-host");//得到时钟
if (IS_ERR(usb_clk)) {
dev_err(&dev->dev, "cannot get usb-bus-host clock/n");
retval = -ENOENT;
goto err_clk;
}
s3c2410_start_hc(dev, hcd);//调用start传输开始
hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);//刚才申请的内存地址利用ioremap转化为虚拟地址
if (!hcd->regs) {
dev_err(&dev->dev, "ioremap failed/n");
retval = -ENOMEM;
goto err_ioremap;
}
ohci_hcd_init(hcd_to_ohci(hcd));//初始化hcd
retval = usb_add_hcd(hcd, dev->resource[1].start, IRQF_DISABLED);//成功添加hcd，指定中断方式
if (retval != 0)
goto err_ioremap;
return 0;
err_ioremap:
s3c2410_stop_hc(dev);
iounmap(hcd->regs);
clk_put(usb_clk);
err_clk:
clk_put(clk);
err_mem:
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
err_put:
usb_put_hcd(hcd);
return retval;
}
/*-------------------------------------------------------------------------*/
static int
ohci_s3c2410_start (struct usb_hcd *hcd)
{
struct ohci_hcd *ohci = hcd_to_ohci (hcd);
int ret;
if ((ret = ohci_init(ohci)) < 0)
return ret;
if ((ret = ohci_run (ohci)) < 0) {
err ("can't start %s", hcd->self.bus_name);
ohci_stop (hcd);
return ret;
}
return 0;
}
static const struct hc_driver ohci_s3c2410_hc_driver = {
.description = hcd_name,
.product_desc = "S3C24XX OHCI",
.hcd_priv_size = sizeof(struct ohci_hcd),
/*
* generic hardware linkage
*/
.irq = ohci_irq,
.flags = HCD_USB11 | HCD_MEMORY,
/*
* basic lifecycle operations
*/
.start = ohci_s3c2410_start,
.stop = ohci_stop,
.shutdown = ohci_shutdown,
/*
* managing i/o requests and associated device resources
*/
.urb_enqueue = ohci_urb_enqueue,
.urb_dequeue = ohci_urb_dequeue,
.endpoint_disable = ohci_endpoint_disable,
/*
* scheduling support
*/
.get_frame_number = ohci_get_frame,
/*
* root hub support
*/
.hub_status_data = ohci_s3c2410_hub_status_data,
.hub_control = ohci_s3c2410_hub_control,
#ifdef CONFIG_PM
.bus_suspend = ohci_bus_suspend,
.bus_resume = ohci_bus_resume,
#endif
.start_port_reset = ohci_start_port_reset,
};
/* device driver */
static int ohci_hcd_s3c2410_drv_probe(struct platform_device *pdev)
{
return usb_hcd_s3c2410_probe(&ohci_s3c2410_hc_driver, pdev);
}
static int ohci_hcd_s3c2410_drv_remove(struct platform_device *pdev)
{
struct usb_hcd *hcd = platform_get_drvdata(pdev);
usb_hcd_s3c2410_remove(hcd, pdev);
return 0;
}
/*平台驱动文件操作*/
static struct platform_driver ohci_hcd_s3c2410_driver = {
.probe = ohci_hcd_s3c2410_drv_probe,
.remove = ohci_hcd_s3c2410_drv_remove,
.shutdown = usb_hcd_platform_shutdown,
/*.suspend = ohci_hcd_s3c2410_drv_suspend, */
/*.resume = ohci_hcd_s3c2410_drv_resume, */
.driver = {
.owner = THIS_MODULE,
.name = "s3c2410-ohci",
},
};
MODULE_ALIAS("platform:s3c2410-ohci");