From 3996a4ffb01f57f82abe6c7e60ac9048dd0c31df Mon Sep 17 00:00:00 2001 From: Vivien Didelot Date: Fri, 30 Oct 2015 18:56:45 -0400 Subject: [PATCH] net: dsa: mv88e6xxx: assert SMI lock It's easy to forget to lock the smi_mutex before calling the low-level _mv88e6xxx_reg_{read,write}, so add a assert_smi_lock function in them. Signed-off-by: Vivien Didelot Acked-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/dsa/mv88e6xxx.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c index 9ee1be20a946..d8866988a88a 100644 --- a/drivers/net/dsa/mv88e6xxx.c +++ b/drivers/net/dsa/mv88e6xxx.c @@ -24,6 +24,16 @@ #include #include "mv88e6xxx.h" +static void assert_smi_lock(struct dsa_switch *ds) +{ + struct mv88e6xxx_priv_state *ps = ds_to_priv(ds); + + if (unlikely(!mutex_is_locked(&ps->smi_mutex))) { + dev_err(ds->master_dev, "SMI lock not held!\n"); + dump_stack(); + } +} + /* If the switch's ADDR[4:0] strap pins are strapped to zero, it will * use all 32 SMI bus addresses on its SMI bus, and all switch registers * will be directly accessible on some {device address,register address} @@ -80,12 +90,13 @@ int __mv88e6xxx_reg_read(struct mii_bus *bus, int sw_addr, int addr, int reg) return ret & 0xffff; } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_reg_read(struct dsa_switch *ds, int addr, int reg) { struct mii_bus *bus = dsa_host_dev_to_mii_bus(ds->master_dev); int ret; + assert_smi_lock(ds); + if (bus == NULL) return -EINVAL; @@ -143,12 +154,13 @@ int __mv88e6xxx_reg_write(struct mii_bus *bus, int sw_addr, int addr, return 0; } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_reg_write(struct dsa_switch *ds, int addr, int reg, u16 val) { struct mii_bus *bus = dsa_host_dev_to_mii_bus(ds->master_dev); + assert_smi_lock(ds); + if (bus == NULL) return -EINVAL; @@ -204,7 +216,6 @@ int mv88e6xxx_set_addr_indirect(struct dsa_switch *ds, u8 *addr) return 0; } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_phy_read(struct dsa_switch *ds, int addr, int regnum) { if (addr >= 0) @@ -212,7 +223,6 @@ static int _mv88e6xxx_phy_read(struct dsa_switch *ds, int addr, int regnum) return 0xffff; } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_phy_write(struct dsa_switch *ds, int addr, int regnum, u16 val) { @@ -538,7 +548,6 @@ out: mutex_unlock(&ps->smi_mutex); } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_stats_wait(struct dsa_switch *ds) { int ret; @@ -553,7 +562,6 @@ static int _mv88e6xxx_stats_wait(struct dsa_switch *ds) return -ETIMEDOUT; } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_stats_snapshot(struct dsa_switch *ds, int port) { int ret; @@ -576,7 +584,6 @@ static int _mv88e6xxx_stats_snapshot(struct dsa_switch *ds, int port) return 0; } -/* Must be called with SMI mutex held */ static void _mv88e6xxx_stats_read(struct dsa_switch *ds, int stat, u32 *val) { u32 _val; @@ -789,7 +796,6 @@ void mv88e6xxx_get_regs(struct dsa_switch *ds, int port, } } -/* Must be called with SMI lock held */ static int _mv88e6xxx_wait(struct dsa_switch *ds, int reg, int offset, u16 mask) { @@ -839,14 +845,12 @@ int mv88e6xxx_eeprom_busy_wait(struct dsa_switch *ds) GLOBAL2_EEPROM_OP_BUSY); } -/* Must be called with SMI lock held */ static int _mv88e6xxx_atu_wait(struct dsa_switch *ds) { return _mv88e6xxx_wait(ds, REG_GLOBAL, GLOBAL_ATU_OP, GLOBAL_ATU_OP_BUSY); } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_phy_read_indirect(struct dsa_switch *ds, int addr, int regnum) { @@ -865,7 +869,6 @@ static int _mv88e6xxx_phy_read_indirect(struct dsa_switch *ds, int addr, return _mv88e6xxx_reg_read(ds, REG_GLOBAL2, GLOBAL2_SMI_DATA); } -/* Must be called with SMI mutex held */ static int _mv88e6xxx_phy_write_indirect(struct dsa_switch *ds, int addr, int regnum, u16 val) { -- 2.20.1