diff mbox series

[v1,1/3] usb: host: npcm7xx: remove USB EHCI host reset sequence

Message ID 20220718122922.9396-2-tmaimon77@gmail.com
State New
Headers show
Series usb: host: npcm7xx-ehci: add Arbel NPCM8XX support and remove reset sequence | expand

Commit Message

Tomer Maimon July 18, 2022, 12:29 p.m. UTC 
Remove USB EHCI host controller reset sequence from NPCM7XX USB EHCI
host probe function because it is done in the NPCM reset driver.

Due to it, NPCM7XX EHCI driver configuration is dependent on NPCM reset.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
---
 drivers/usb/host/Kconfig        |  2 +-
 drivers/usb/host/ehci-npcm7xx.c | 47 ---------------------------------
 2 files changed, 1 insertion(+), 48 deletions(-)

Comments

Arnd Bergmann July 18, 2022, 12:38 p.m. UTC | #1 
On Mon, Jul 18, 2022 at 2:29 PM Tomer Maimon <tmaimon77@gmail.com> wrote:
>
>  config USB_EHCI_HCD_NPCM7XX
>         tristate "Support for Nuvoton NPCM7XX on-chip EHCI USB controller"
> -       depends on (USB_EHCI_HCD && ARCH_NPCM7XX) || COMPILE_TEST
> +       depends on (USB_EHCI_HCD && ARCH_NPCM7XX && RESET_NPCM) || COMPILE_TEST
>         default y if (USB_EHCI_HCD && ARCH_NPCM7XX)
>         help
>           Enables support for the on-chip EHCI controller on

I would leave out this Kconfig change, there is really no need to enforce
this specific dependency.  It is expected that a device driver has dependencies
on several other subsystems (irqchip, reset, pinctrl, clock, ....) and will only
work if the required drivers are also built for the same kernel.

Also, forcing the USB driver to be a loadable module when the reset driver
is a module (rather than built-in) does not guarantee that they are initialized
in the correct order. If only the USB driver is built-in and the reset driver is
a module, or both are loadable modules and USB gets loaded first, then
the probe() function should notice this and return -EPROBE_DEFER so
it will be retried after the reset driver is successfully loaded.

        Arnd
diff mbox series

Patch

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 682b3d2da623..e05e2cf806f8 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -206,7 +206,7 @@  config USB_EHCI_FSL
 
 config USB_EHCI_HCD_NPCM7XX
 	tristate "Support for Nuvoton NPCM7XX on-chip EHCI USB controller"
-	depends on (USB_EHCI_HCD && ARCH_NPCM7XX) || COMPILE_TEST
+	depends on (USB_EHCI_HCD && ARCH_NPCM7XX && RESET_NPCM) || COMPILE_TEST
 	default y if (USB_EHCI_HCD && ARCH_NPCM7XX)
 	help
 	  Enables support for the on-chip EHCI controller on
diff --git a/drivers/usb/host/ehci-npcm7xx.c b/drivers/usb/host/ehci-npcm7xx.c
index 6b5a7a873e01..955e7c8f3db8 100644
--- a/drivers/usb/host/ehci-npcm7xx.c
+++ b/drivers/usb/host/ehci-npcm7xx.c
@@ -28,13 +28,6 @@ 
 #define DRIVER_DESC "EHCI npcm7xx driver"
 
 static const char hcd_name[] = "npcm7xx-ehci";
-
-#define  USB2PHYCTL_OFFSET 0x144
-
-#define  IPSRST2_OFFSET 0x24
-#define  IPSRST3_OFFSET 0x34
-
-
 static struct hc_driver __read_mostly ehci_npcm7xx_hc_driver;
 
 static int __maybe_unused ehci_npcm7xx_drv_suspend(struct device *dev)
@@ -60,52 +53,12 @@  static int npcm7xx_ehci_hcd_drv_probe(struct platform_device *pdev)
 {
 	struct usb_hcd *hcd;
 	struct resource *res;
-	struct regmap *gcr_regmap;
-	struct regmap *rst_regmap;
 	const struct hc_driver *driver = &ehci_npcm7xx_hc_driver;
 	int irq;
 	int retval;
 
 	dev_dbg(&pdev->dev,	"initializing npcm7xx ehci USB Controller\n");
 
-	gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
-	if (IS_ERR(gcr_regmap)) {
-		dev_err(&pdev->dev, "%s: failed to find nuvoton,npcm750-gcr\n",
-			__func__);
-		return PTR_ERR(gcr_regmap);
-	}
-
-	rst_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-rst");
-	if (IS_ERR(rst_regmap)) {
-		dev_err(&pdev->dev, "%s: failed to find nuvoton,npcm750-rst\n",
-			__func__);
-		return PTR_ERR(rst_regmap);
-	}
-
-	/********* phy init  ******/
-	// reset usb host
-	regmap_update_bits(rst_regmap, IPSRST2_OFFSET,
-			(0x1 << 26), (0x1 << 26));
-	regmap_update_bits(rst_regmap, IPSRST3_OFFSET,
-			(0x1 << 25), (0x1 << 25));
-	regmap_update_bits(gcr_regmap, USB2PHYCTL_OFFSET,
-			(0x1 << 28), 0);
-
-	udelay(1);
-
-	// enable phy
-	regmap_update_bits(rst_regmap, IPSRST3_OFFSET,
-			(0x1 << 25), 0);
-
-	udelay(50); // enable phy
-
-	regmap_update_bits(gcr_regmap, USB2PHYCTL_OFFSET,
-			(0x1 << 28), (0x1 << 28));
-
-	// enable host
-	regmap_update_bits(rst_regmap, IPSRST2_OFFSET,
-			(0x1 << 26), 0);
-
 	if (usb_disabled())
 		return -ENODEV;