ALSA: emu10k1: fix locking in snd_emu1010_fpga_link_dst_src_write()

This is a multi-register operation, which must be locked in its
entirety.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230428095941.1706278-5-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/pci/emu10k1/io.c b/sound/pci/emu10k1/io.c
index cfb96a6..aee84c3 100644 (file)
--- a/sound/pci/emu10k1/io.c
+++ b/sound/pci/emu10k1/io.c
@@ -233,16 +233,13 @@ int snd_emu10k1_i2c_write(struct snd_emu10k1 *emu,
        return err;
 }
 
-void snd_emu1010_fpga_write(struct snd_emu10k1 *emu, u32 reg, u32 value)
+static void snd_emu1010_fpga_write_locked(struct snd_emu10k1 *emu, u32 reg, u32 value)
 {
-       unsigned long flags;
-
        if (snd_BUG_ON(reg > 0x3f))
                return;
        reg += 0x40; /* 0x40 upwards are registers. */
        if (snd_BUG_ON(value > 0x3f)) /* 0 to 0x3f are values */
                return;
-       spin_lock_irqsave(&emu->emu_lock, flags);
        outw(reg, emu->port + A_GPIO);
        udelay(10);
        outw(reg | 0x80, emu->port + A_GPIO);  /* High bit clocks the value into the fpga. */
@@ -250,6 +247,14 @@ void snd_emu1010_fpga_write(struct snd_emu10k1 *emu, u32 reg, u32 value)
        outw(value, emu->port + A_GPIO);
        udelay(10);
        outw(value | 0x80 , emu->port + A_GPIO);  /* High bit clocks the value into the fpga. */
+}
+
+void snd_emu1010_fpga_write(struct snd_emu10k1 *emu, u32 reg, u32 value)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&emu->emu_lock, flags);
+       snd_emu1010_fpga_write_locked(emu, reg, value);
        spin_unlock_irqrestore(&emu->emu_lock, flags);
 }
 
@@ -276,14 +281,18 @@ void snd_emu1010_fpga_read(struct snd_emu10k1 *emu, u32 reg, u32 *value)
  */
 void snd_emu1010_fpga_link_dst_src_write(struct snd_emu10k1 *emu, u32 dst, u32 src)
 {
+       unsigned long flags;
+
        if (snd_BUG_ON(dst & ~0x71f))
                return;
        if (snd_BUG_ON(src & ~0x71f))
                return;
-       snd_emu1010_fpga_write(emu, EMU_HANA_DESTHI, dst >> 8);
-       snd_emu1010_fpga_write(emu, EMU_HANA_DESTLO, dst & 0x1f);
-       snd_emu1010_fpga_write(emu, EMU_HANA_SRCHI, src >> 8);
-       snd_emu1010_fpga_write(emu, EMU_HANA_SRCLO, src & 0x1f);
+       spin_lock_irqsave(&emu->emu_lock, flags);
+       snd_emu1010_fpga_write_locked(emu, EMU_HANA_DESTHI, dst >> 8);
+       snd_emu1010_fpga_write_locked(emu, EMU_HANA_DESTLO, dst & 0x1f);
+       snd_emu1010_fpga_write_locked(emu, EMU_HANA_SRCHI, src >> 8);
+       snd_emu1010_fpga_write_locked(emu, EMU_HANA_SRCLO, src & 0x1f);
+       spin_unlock_irqrestore(&emu->emu_lock, flags);
 }
 
 void snd_emu10k1_intr_enable(struct snd_emu10k1 *emu, unsigned int intrenb)