Re: [PATCH 1/7] soc: renesas: r9a06g032-sysctrl: Export function to get H2MODE from CFG_USB register

Hi Geert,

Oops, my bad I removed all people from the email previously.
Re-added them on this reply. 

On Mon, 7 Nov 2022 20:23:06 +0100
Geert Uytterhoeven [off-list ref] wrote:

Hi Hervé,

On Mon, Nov 7, 2022 at 5:54 PM Herve Codina [off-list ref] wrote:

quoted

On Mon, 7 Nov 2022 15:40:53 +0100
Geert Uytterhoeven [off-list ref] wrote:  

quoted

On Mon, Nov 7, 2022 at 2:59 PM Herve Codina [off-list ref] wrote:  

quoted

The CFG_USB register is located within the system controller.

We need a helper to get the H2MODE value from the CFG_USB register
without syscon.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>  

quoted

--- a/drivers/clk/renesas/r9a06g032-clocks.c
+++ b/drivers/clk/renesas/r9a06g032-clocks.c

@@ -25,6 +25,8 @@
 #include <linux/spinlock.h>
 #include <dt-bindings/clock/r9a06g032-sysctrl.h>

+#define R9A06G032_SYSCTRL_USB    0x00
+#define R9A06G032_SYSCTRL_USB_H2MODE  (1<<1)
 #define R9A06G032_SYSCTRL_DMAMUX 0xA0

 struct r9a06g032_gate {

@@ -341,6 +343,22 @@ int r9a06g032_sysctrl_set_dmamux(u32 mask, u32 val)
 }
 EXPORT_SYMBOL_GPL(r9a06g032_sysctrl_set_dmamux);

+
+/* Exported helper to get the H2MODE bit from USB register */
+int r9a06g032_sysctrl_get_usb_h2mode(bool *h2mode)
+{
+       u32 usb;
+
+       if (!sysctrl_priv)
+               return -EPROBE_DEFER;
+
+       usb = readl(sysctrl_priv->reg + R9A06G032_SYSCTRL_USB);
+       *h2mode = (usb & R9A06G032_SYSCTRL_USB_H2MODE) ? true : false;
+
+       return 0;  

Perhaps not pass *h2mode, but just return USB_ROLE_{HOST,DEVICE}
(enum usb_role in <linux/usb/role.h>), or a negative error code?  

Yes, good idea.
I will also rename the function :
  enum usb_role r9a06g032_sysctrl_get_usb_role(void);

Is that ok for you or do you prefer that I keep the previous name ?  

r9a06g032_sysctrl_get_usb_role() sounds fine!
But it should return "int", as the return value can be a negative error code,
too.

All right, I will do that in v2 series.

Thanks,
Hervé

-- 
Hervé Codina, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com