Re: [PATCH v3] PCI: shpchp: Remove hpc_ops

[ngn <ngn@ngn.tf>]

On Thu, Aug 01, 2024 at 07:08:52PM -0500, Bjorn Helgaas wrote:
> On Tue, Jul 23, 2024 at 02:43:25PM +0300, ngn wrote:
> > Remove the hpc_ops struct from shpchp. This struct is unnecessary as
> > no other hotplug controller implements it. A similar thing has already
> > been done in pciehp with commit 82a9e79ef132 ("PCI: pciehp: remove hpc_ops")
> 
> > +++ b/drivers/pci/hotplug/shpchp_hpc.c
> > @@ -167,7 +167,6 @@
> >  
> >  static irqreturn_t shpc_isr(int irq, void *dev_id);
> >  static void start_int_poll_timer(struct controller *ctrl, int sec);
> > -static int hpc_check_cmd_status(struct controller *ctrl);
> >  
> >  static inline u8 shpc_readb(struct controller *ctrl, int reg)
> >  {
> > @@ -317,7 +316,7 @@ static int shpc_write_cmd(struct slot *slot, u8 t_slot, u8 cmd)
> >  	if (retval)
> >  		goto out;
> >  
> > -	cmd_status = hpc_check_cmd_status(slot->ctrl);
> > +	cmd_status = shpchp_check_cmd_status(slot->ctrl);
> 
> This rename looks like it should be a separate patch because it's not
> part of removing hpc_ops.

I think hpc_check_cmd_status meant to be a part of the hpc_ops struct.
Here is the original struct:

struct hpc_ops {
	int (*power_on_slot)(struct slot *slot);
	int (*slot_enable)(struct slot *slot);
	int (*slot_disable)(struct slot *slot);
	int (*set_bus_speed_mode)(struct slot *slot, enum pci_bus_speed speed);
	int (*get_power_status)(struct slot *slot, u8 *status);
	int (*get_attention_status)(struct slot *slot, u8 *status);
	int (*set_attention_status)(struct slot *slot, u8 status);
	int (*get_latch_status)(struct slot *slot, u8 *status);
	int (*get_adapter_status)(struct slot *slot, u8 *status);
	int (*get_adapter_speed)(struct slot *slot, enum pci_bus_speed *speed);
	int (*get_prog_int)(struct slot *slot, u8 *prog_int);
	int (*query_power_fault)(struct slot *slot);
	void (*green_led_on)(struct slot *slot);
	void (*green_led_off)(struct slot *slot);
	void (*green_led_blink)(struct slot *slot);
	void (*release_ctlr)(struct controller *ctrl);
	int (*check_cmd_status)(struct controller *ctrl);
};

As you can see it contains a pointer for check_cmd_status function,
however the hpc_check_cmd_status was never assigned to it:

static const struct hpc_ops shpchp_hpc_ops = {
	.power_on_slot			= hpc_power_on_slot,
	.slot_enable			= hpc_slot_enable,
	.slot_disable			= hpc_slot_disable,
	.set_bus_speed_mode		= hpc_set_bus_speed_mode,
	.set_attention_status	= hpc_set_attention_status,
	.get_power_status		= hpc_get_power_status,
	.get_attention_status	= hpc_get_attention_status,
	.get_latch_status		= hpc_get_latch_status,
	.get_adapter_status		= hpc_get_adapter_status,

	.get_adapter_speed		= hpc_get_adapter_speed,
	.get_prog_int			= hpc_get_prog_int,

	.query_power_fault		= hpc_query_power_fault,
	.green_led_on			= hpc_set_green_led_on,
	.green_led_off			= hpc_set_green_led_off,
	.green_led_blink		= hpc_set_green_led_blink,

	.release_ctlr			= hpc_release_ctlr,
};

Which made me believe that this function supposed to be a part of the
hpc_ops struct and whoever wrote the code added a pointer for it but
then they forgot to assign the function to it during the actual
definition of the struct. So I renamed it anyway.