Commit ca8934f8 authored by Heiner Kallweit's avatar Heiner Kallweit Committed by Jakub Kicinski
Browse files

net: phy: fixed_phy: replace IDA with a bitmap 



Size of array fmb_fixed_phys is small, so we can use a simple bitmap
instead of an IDA to manage dynamic allocation of fixed PHY's.
find_first_zero_bit() isn't atomic, so we need the loop to rule out
double allocation of a PHY address.

Suggested-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Tested-by: default avatarMaxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: default avatarMaxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/d4614463-d532-41fc-92e9-ef97107aceb5@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 511cb452

drivers/net/phy/fixed_phy.c

+17 −7
Original line number Diff line number Diff line
@@ -16,7 +16,6 @@ 
#include <linux/err.h>

#include <linux/slab.h>

#include <linux/of.h>

#include <linux/idr.h>

#include <linux/netdevice.h>



#include "swphy.h"
@@ -32,13 +31,13 @@ struct fixed_phy { 
	int (*link_update)(struct net_device *, struct fixed_phy_status *);

};



static DECLARE_BITMAP(fixed_phy_ids, NUM_FP);

static struct fixed_phy fmb_fixed_phys[NUM_FP];

static struct mii_bus *fmb_mii_bus;

static DEFINE_IDA(phy_fixed_ida);



static struct fixed_phy *fixed_phy_find(int addr)

{

	return ida_exists(&phy_fixed_ida, addr) ? fmb_fixed_phys + addr : NULL;

	return test_bit(addr, fixed_phy_ids) ? fmb_fixed_phys + addr : NULL;

}



int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier)
@@ -113,7 +112,20 @@ static void fixed_phy_del(int phy_addr) 
		return;



	memset(fp, 0, sizeof(*fp));

	ida_free(&phy_fixed_ida, phy_addr);

	clear_bit(phy_addr, fixed_phy_ids);

}



static int fixed_phy_get_free_addr(void)

{

	int addr;



	do {

		addr = find_first_zero_bit(fixed_phy_ids, NUM_FP);

		if (addr == NUM_FP)

			return -ENOSPC;

	} while (test_and_set_bit(addr, fixed_phy_ids));



	return addr;

}



struct phy_device *fixed_phy_register(const struct fixed_phy_status *status,
@@ -131,7 +143,7 @@ struct phy_device *fixed_phy_register(const struct fixed_phy_status *status, 
		return ERR_PTR(-EPROBE_DEFER);



	/* Get the next available PHY address, up to NUM_FP */

	phy_addr = ida_alloc_max(&phy_fixed_ida, NUM_FP - 1, GFP_KERNEL);

	phy_addr = fixed_phy_get_free_addr();

	if (phy_addr < 0)

		return ERR_PTR(phy_addr);
@@ -210,8 +222,6 @@ static void __exit fixed_mdio_bus_exit(void) 
{

	mdiobus_unregister(fmb_mii_bus);

	mdiobus_free(fmb_mii_bus);



	ida_destroy(&phy_fixed_ida);

}

module_exit(fixed_mdio_bus_exit);