Re: [PATCH v2] usb: dwc2: add pci_device_id driver_data parse support
From: zhuyinbo
Date: Fri Jun 09 2023 - 05:13:57 EST
在 2023/6/9 下午2:13, Greg Kroah-Hartman 写道:
On Fri, Jun 09, 2023 at 10:50:47AM +0800, Yinbo Zhu wrote:
The dwc2 driver has everything we need to run in PCI mode except
for pci_device_id driver_data parse. With that to set Loongson
dwc2 element and added identified as PCI_VENDOR_ID_LOONGSON
and PCI_DEVICE_ID_LOONGSON_DWC2 in dwc2_pci_ids, the Loongson
dwc2 controller will work.
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
---
Change in v2:
1. Move the dwc2 pci ID from pci_ids.h to params.c.
2. Add some code logic to ensure that the current device is
a PCI device.
3. Fix the compile issue when dwc2 pci driver as module.
drivers/usb/dwc2/core.h | 1 +
drivers/usb/dwc2/params.c | 39 ++++++++++++++++++++++++++++++++++++++-
drivers/usb/dwc2/pci.c | 14 +-------------
3 files changed, 40 insertions(+), 14 deletions(-)
diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 0bb4c0c845bf..c92a1da46a01 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -1330,6 +1330,7 @@ irqreturn_t dwc2_handle_common_intr(int irq, void *dev);
/* The device ID match table */
extern const struct of_device_id dwc2_of_match_table[];
extern const struct acpi_device_id dwc2_acpi_match[];
+extern const struct pci_device_id dwc2_pci_ids[];
int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg);
int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg);
diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
index 21d16533bd2f..6b68a8830781 100644
--- a/drivers/usb/dwc2/params.c
+++ b/drivers/usb/dwc2/params.c
@@ -7,9 +7,14 @@
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/usb/of.h>
+#include <linux/pci_ids.h>
+#include <linux/pci.h>
#include "core.h"
+#define PCI_PRODUCT_ID_HAPS_HSOTG 0xabc0
+#define PCI_DEVICE_ID_LOONGSON_DWC2 0x7a04
+
static void dwc2_set_bcm_params(struct dwc2_hsotg *hsotg)
{
struct dwc2_core_params *p = &hsotg->params;
@@ -55,6 +60,14 @@ static void dwc2_set_jz4775_params(struct dwc2_hsotg *hsotg)
!device_property_read_bool(hsotg->dev, "disable-over-current");
}
+static void dwc2_set_loongson_params(struct dwc2_hsotg *hsotg)
+{
+ struct dwc2_core_params *p = &hsotg->params;
+
+ p->phy_utmi_width = 8;
+ p->power_down = DWC2_POWER_DOWN_PARAM_PARTIAL;
+}
+
static void dwc2_set_x1600_params(struct dwc2_hsotg *hsotg)
{
struct dwc2_core_params *p = &hsotg->params;
@@ -281,6 +294,23 @@ const struct acpi_device_id dwc2_acpi_match[] = {
};
MODULE_DEVICE_TABLE(acpi, dwc2_acpi_match);
+const struct pci_device_id dwc2_pci_ids[] = {
+ {
+ PCI_DEVICE(PCI_VENDOR_ID_SYNOPSYS, PCI_PRODUCT_ID_HAPS_HSOTG),
+ },
+ {
+ PCI_DEVICE(PCI_VENDOR_ID_STMICRO,
+ PCI_DEVICE_ID_STMICRO_USB_OTG),
+ },
+ {
+ PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, PCI_DEVICE_ID_LOONGSON_DWC2),
+ .driver_data = (unsigned long)dwc2_set_loongson_params,
+ },
+ { /* end: all zeroes */ }
+};
+MODULE_DEVICE_TABLE(pci, dwc2_pci_ids);
+EXPORT_SYMBOL_GPL(dwc2_pci_ids);
+
static void dwc2_set_param_otg_cap(struct dwc2_hsotg *hsotg)
{
switch (hsotg->hw_params.op_mode) {
@@ -927,13 +957,20 @@ int dwc2_init_params(struct dwc2_hsotg *hsotg)
if (match && match->data) {
set_params = match->data;
set_params(hsotg);
- } else {
+ } else if (!match) {
const struct acpi_device_id *amatch;
+ const struct pci_device_id *pmatch = NULL;
amatch = acpi_match_device(dwc2_acpi_match, hsotg->dev);
if (amatch && amatch->driver_data) {
set_params = (set_params_cb)amatch->driver_data;
set_params(hsotg);
+ } else if (!amatch)
+ pmatch = pci_match_id(dwc2_pci_ids, to_pci_dev(hsotg->dev->parent));
At this point in time, how can you guarantee that the parent device
really is a PCI one? This function is being called from a platform
device callback, and platform devices should NEVER be a child of a PCI
device, as that's not how PCI or platform devices work.
So how is this even possible?
confused,
Hi greg k-h,
My current considerations are based on that the dwc2 drivers support
three types of devices, they are Platform device / ACPI device / PCI
device, and The dwc2/platform.c can all cover the three type dwc2
device, no matter how it is registered.
So, when a dwc2 device wasn't platform device and acpi device and It
will be a PCI device, and the the dwc2/pci.c will register a dwc2
platform device that dwc2 device is a device that in dwc2/platform.c's
dwc2_driver_probe. the "&dwc2->dev->parent" is the "hsotg->dev->parent"
and it was also the &pci->dev.
So, We can use "to_pci_dev(hsotg->dev->parent)" to gain a dwc2 pci
device.
1) DWC2 PCI device driver (drivers/usb/dwc2/pci.c) :
static int dwc2_pci_probe(struct pci_dev *pci,
const struct pci_device_id *id)
{
...
struct platform_device *dwc2;
...
struct device *dev = &pci->dev;
...
dwc2 = platform_device_alloc("dwc2", PLATFORM_DEVID_AUTO);
//"dwc2" was used to match dwc2 platform driver
...
dwc2->dev.parent = dev;
...
}
2) DWC2 PLATFROM driver (drivers/usb/dwc2/platform.c) :
// This driver cover pci type device.
static const char dwc2_driver_name[] = "dwc2";
static struct platform_driver dwc2_platform_driver = {
.driver = {
.name = dwc2_driver_name,
//"dwc2" was used to match pci type dwc2 device
...
},
.probe = dwc2_driver_probe,
.remove = dwc2_driver_remove,
.shutdown = dwc2_driver_shutdown,
};
static int dwc2_driver_probe(struct platform_device *dev)
{
// The dev is the "dwc2" platform device in dwc2/pci.c driver.
struct dwc2_hsotg *hsotg;
...
hsotg->dev = &dev->dev;
// The hsotg->dev->parent or &dev->dev->parent is the &pci->dev in
// dwc2/pci.c driver.
...
}
Thanks,
Yinbo