diff mbox series

[v2] ALSA: rme9652: use explicitly signed char

Message ID 20221025000313.546261-1-Jason@zx2c4.com
State New
Headers
Series [v2] ALSA: rme9652: use explicitly signed char |

Commit Message

Jason A. Donenfeld Oct. 25, 2022, 12:03 a.m. UTC 
  With char becoming unsigned by default, and with `char` alone being
ambiguous and based on architecture, signed chars need to be marked
explicitly as such. This fixes warnings like:

sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: alsa-devel@alsa-project.org
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 sound/pci/rme9652/hdsp.c    | 26 +++++++++++++-------------
 sound/pci/rme9652/rme9652.c | 22 +++++++++++-----------
 2 files changed, 24 insertions(+), 24 deletions(-)

Comments

Takashi Iwai Oct. 25, 2022, 6:21 a.m. UTC | #1 
On Tue, 25 Oct 2022 02:03:13 +0200,
Jason A. Donenfeld wrote:
> 
> With char becoming unsigned by default, and with `char` alone being
> ambiguous and based on architecture, signed chars need to be marked
> explicitly as such. This fixes warnings like:
> 
> sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> 
> Cc: Jaroslav Kysela <perex@perex.cz>
> Cc: Takashi Iwai <tiwai@suse.com>
> Cc: alsa-devel@alsa-project.org
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Applied now.  Thanks!


Takashi
Jason A. Donenfeld Oct. 25, 2022, 12:08 p.m. UTC | #2 
On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> On Tue, 25 Oct 2022 02:03:13 +0200,
> Jason A. Donenfeld wrote:
> > 
> > With char becoming unsigned by default, and with `char` alone being
> > ambiguous and based on architecture, signed chars need to be marked
> > explicitly as such. This fixes warnings like:
> > 
> > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > 
> > Cc: Jaroslav Kysela <perex@perex.cz>
> > Cc: Takashi Iwai <tiwai@suse.com>
> > Cc: alsa-devel@alsa-project.org
> > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> 
> Applied now.  Thanks!

Thanks. For this and the other patch, applied for 6.1 or 6.2?

Jason
Takashi Iwai Oct. 25, 2022, 12:48 p.m. UTC | #3 
On Tue, 25 Oct 2022 14:08:29 +0200,
Jason A. Donenfeld wrote:
> 
> On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > On Tue, 25 Oct 2022 02:03:13 +0200,
> > Jason A. Donenfeld wrote:
> > > 
> > > With char becoming unsigned by default, and with `char` alone being
> > > ambiguous and based on architecture, signed chars need to be marked
> > > explicitly as such. This fixes warnings like:
> > > 
> > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > 
> > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > Cc: Takashi Iwai <tiwai@suse.com>
> > > Cc: alsa-devel@alsa-project.org
> > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > 
> > Applied now.  Thanks!
> 
> Thanks. For this and the other patch, applied for 6.1 or 6.2?

I applied for 6.2.  Was it an action that has to be fixed for 6.1?
If so, I still can shuffle.


thanks,

Takashi
Jason A. Donenfeld Oct. 25, 2022, 12:54 p.m. UTC | #4 
On Tue, Oct 25, 2022 at 2:48 PM Takashi Iwai <tiwai@suse.de> wrote:
>
> On Tue, 25 Oct 2022 14:08:29 +0200,
> Jason A. Donenfeld wrote:
> >
> > On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > > On Tue, 25 Oct 2022 02:03:13 +0200,
> > > Jason A. Donenfeld wrote:
> > > >
> > > > With char becoming unsigned by default, and with `char` alone being
> > > > ambiguous and based on architecture, signed chars need to be marked
> > > > explicitly as such. This fixes warnings like:
> > > >
> > > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > >
> > > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > > Cc: Takashi Iwai <tiwai@suse.com>
> > > > Cc: alsa-devel@alsa-project.org
> > > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > >
> > > Applied now.  Thanks!
> >
> > Thanks. For this and the other patch, applied for 6.1 or 6.2?
>
> I applied for 6.2.  Was it an action that has to be fixed for 6.1?
> If so, I still can shuffle.

Well, this is code that's broken currently on ARM platforms, for
example, where char is already unsigned. So it's arguably a fix for
6.1.

(And if you're in fact not going to take it for 6.1, I'm supposed to
take it through my unsigned-char tree for 6.2.)

Jason
Takashi Iwai Oct. 25, 2022, 1:11 p.m. UTC | #5 
On Tue, 25 Oct 2022 14:54:54 +0200,
Jason A. Donenfeld wrote:
> 
> On Tue, Oct 25, 2022 at 2:48 PM Takashi Iwai <tiwai@suse.de> wrote:
> >
> > On Tue, 25 Oct 2022 14:08:29 +0200,
> > Jason A. Donenfeld wrote:
> > >
> > > On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > > > On Tue, 25 Oct 2022 02:03:13 +0200,
> > > > Jason A. Donenfeld wrote:
> > > > >
> > > > > With char becoming unsigned by default, and with `char` alone being
> > > > > ambiguous and based on architecture, signed chars need to be marked
> > > > > explicitly as such. This fixes warnings like:
> > > > >
> > > > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > > >
> > > > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > > > Cc: Takashi Iwai <tiwai@suse.com>
> > > > > Cc: alsa-devel@alsa-project.org
> > > > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > > >
> > > > Applied now.  Thanks!
> > >
> > > Thanks. For this and the other patch, applied for 6.1 or 6.2?
> >
> > I applied for 6.2.  Was it an action that has to be fixed for 6.1?
> > If so, I still can shuffle.
> 
> Well, this is code that's broken currently on ARM platforms, for
> example, where char is already unsigned. So it's arguably a fix for
> 6.1.

Fair enough, I'll apply for 6.1, then.


Takashi
Takashi Iwai Oct. 25, 2022, 1:14 p.m. UTC | #6 
On Tue, 25 Oct 2022 15:11:39 +0200,
Takashi Iwai wrote:
> 
> On Tue, 25 Oct 2022 14:54:54 +0200,
> Jason A. Donenfeld wrote:
> > 
> > On Tue, Oct 25, 2022 at 2:48 PM Takashi Iwai <tiwai@suse.de> wrote:
> > >
> > > On Tue, 25 Oct 2022 14:08:29 +0200,
> > > Jason A. Donenfeld wrote:
> > > >
> > > > On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > > > > On Tue, 25 Oct 2022 02:03:13 +0200,
> > > > > Jason A. Donenfeld wrote:
> > > > > >
> > > > > > With char becoming unsigned by default, and with `char` alone being
> > > > > > ambiguous and based on architecture, signed chars need to be marked
> > > > > > explicitly as such. This fixes warnings like:
> > > > > >
> > > > > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > > > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > > > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > > > >
> > > > > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > > > > Cc: Takashi Iwai <tiwai@suse.com>
> > > > > > Cc: alsa-devel@alsa-project.org
> > > > > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > > > >
> > > > > Applied now.  Thanks!
> > > >
> > > > Thanks. For this and the other patch, applied for 6.1 or 6.2?
> > >
> > > I applied for 6.2.  Was it an action that has to be fixed for 6.1?
> > > If so, I still can shuffle.
> > 
> > Well, this is code that's broken currently on ARM platforms, for
> > example, where char is already unsigned. So it's arguably a fix for
> > 6.1.
> 
> Fair enough, I'll apply for 6.1, then.

... and in that case, it deserves for Cc-to-stable, IMO, as it's a fix
to be done for older kernels, too.  Then it'd be clearly a 6.1
material.


Takashi
Jason A. Donenfeld Oct. 25, 2022, 1:14 p.m. UTC | #7 
On Tue, Oct 25, 2022 at 3:14 PM Takashi Iwai <tiwai@suse.de> wrote:
>
> On Tue, 25 Oct 2022 15:11:39 +0200,
> Takashi Iwai wrote:
> >
> > On Tue, 25 Oct 2022 14:54:54 +0200,
> > Jason A. Donenfeld wrote:
> > >
> > > On Tue, Oct 25, 2022 at 2:48 PM Takashi Iwai <tiwai@suse.de> wrote:
> > > >
> > > > On Tue, 25 Oct 2022 14:08:29 +0200,
> > > > Jason A. Donenfeld wrote:
> > > > >
> > > > > On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > > > > > On Tue, 25 Oct 2022 02:03:13 +0200,
> > > > > > Jason A. Donenfeld wrote:
> > > > > > >
> > > > > > > With char becoming unsigned by default, and with `char` alone being
> > > > > > > ambiguous and based on architecture, signed chars need to be marked
> > > > > > > explicitly as such. This fixes warnings like:
> > > > > > >
> > > > > > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > > > > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > > > > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > > > > >
> > > > > > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > > > > > Cc: Takashi Iwai <tiwai@suse.com>
> > > > > > > Cc: alsa-devel@alsa-project.org
> > > > > > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > > > > >
> > > > > > Applied now.  Thanks!
> > > > >
> > > > > Thanks. For this and the other patch, applied for 6.1 or 6.2?
> > > >
> > > > I applied for 6.2.  Was it an action that has to be fixed for 6.1?
> > > > If so, I still can shuffle.
> > >
> > > Well, this is code that's broken currently on ARM platforms, for
> > > example, where char is already unsigned. So it's arguably a fix for
> > > 6.1.
> >
> > Fair enough, I'll apply for 6.1, then.
>
> ... and in that case, it deserves for Cc-to-stable, IMO, as it's a fix
> to be done for older kernels, too.  Then it'd be clearly a 6.1
> material.

Fine by me if you want to add that (for this and the other patch).
Takashi Iwai Oct. 25, 2022, 1:17 p.m. UTC | #8 
On Tue, 25 Oct 2022 15:14:54 +0200,
Jason A. Donenfeld wrote:
> 
> On Tue, Oct 25, 2022 at 3:14 PM Takashi Iwai <tiwai@suse.de> wrote:
> >
> > On Tue, 25 Oct 2022 15:11:39 +0200,
> > Takashi Iwai wrote:
> > >
> > > On Tue, 25 Oct 2022 14:54:54 +0200,
> > > Jason A. Donenfeld wrote:
> > > >
> > > > On Tue, Oct 25, 2022 at 2:48 PM Takashi Iwai <tiwai@suse.de> wrote:
> > > > >
> > > > > On Tue, 25 Oct 2022 14:08:29 +0200,
> > > > > Jason A. Donenfeld wrote:
> > > > > >
> > > > > > On Tue, Oct 25, 2022 at 08:21:55AM +0200, Takashi Iwai wrote:
> > > > > > > On Tue, 25 Oct 2022 02:03:13 +0200,
> > > > > > > Jason A. Donenfeld wrote:
> > > > > > > >
> > > > > > > > With char becoming unsigned by default, and with `char` alone being
> > > > > > > > ambiguous and based on architecture, signed chars need to be marked
> > > > > > > > explicitly as such. This fixes warnings like:
> > > > > > > >
> > > > > > > > sound/pci/rme9652/hdsp.c:3953 hdsp_channel_buffer_location() warn: 'hdsp->channel_map[channel]' is unsigned
> > > > > > > > sound/pci/rme9652/hdsp.c:4153 snd_hdsp_channel_info() warn: impossible condition '(hdsp->channel_map[channel] < 0) => (0-255 < 0)'
> > > > > > > > sound/pci/rme9652/rme9652.c:1833 rme9652_channel_buffer_location() warn: 'rme9652->channel_map[channel]' is unsigned
> > > > > > > >
> > > > > > > > Cc: Jaroslav Kysela <perex@perex.cz>
> > > > > > > > Cc: Takashi Iwai <tiwai@suse.com>
> > > > > > > > Cc: alsa-devel@alsa-project.org
> > > > > > > > Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> > > > > > >
> > > > > > > Applied now.  Thanks!
> > > > > >
> > > > > > Thanks. For this and the other patch, applied for 6.1 or 6.2?
> > > > >
> > > > > I applied for 6.2.  Was it an action that has to be fixed for 6.1?
> > > > > If so, I still can shuffle.
> > > >
> > > > Well, this is code that's broken currently on ARM platforms, for
> > > > example, where char is already unsigned. So it's arguably a fix for
> > > > 6.1.
> > >
> > > Fair enough, I'll apply for 6.1, then.
> >
> > ... and in that case, it deserves for Cc-to-stable, IMO, as it's a fix
> > to be done for older kernels, too.  Then it'd be clearly a 6.1
> > material.
> 
> Fine by me if you want to add that (for this and the other patch).

OK, done.


Takashi
diff mbox series

Patch

diff --git a/sound/pci/rme9652/hdsp.c b/sound/pci/rme9652/hdsp.c
index dcc43a81ae0e..65add92c88aa 100644
--- a/sound/pci/rme9652/hdsp.c
+++ b/sound/pci/rme9652/hdsp.c
@@ -433,7 +433,7 @@  struct hdsp_midi {
     struct snd_rawmidi           *rmidi;
     struct snd_rawmidi_substream *input;
     struct snd_rawmidi_substream *output;
-    char                     istimer; /* timer in use */
+    signed char		     istimer; /* timer in use */
     struct timer_list	     timer;
     spinlock_t               lock;
     int			     pending;
@@ -480,7 +480,7 @@  struct hdsp {
 	pid_t                 playback_pid;
 	int                   running;
 	int                   system_sample_rate;
-	const char           *channel_map;
+	const signed char    *channel_map;
 	int                   dev;
 	int                   irq;
 	unsigned long         port;
@@ -502,7 +502,7 @@  struct hdsp {
    where the data for that channel can be read/written from/to.
 */
 
-static const char channel_map_df_ss[HDSP_MAX_CHANNELS] = {
+static const signed char channel_map_df_ss[HDSP_MAX_CHANNELS] = {
 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
 	18, 19, 20, 21, 22, 23, 24, 25
 };
@@ -517,7 +517,7 @@  static const char channel_map_mf_ss[HDSP_MAX_CHANNELS] = { /* Multiface */
 	-1, -1, -1, -1, -1, -1, -1, -1
 };
 
-static const char channel_map_ds[HDSP_MAX_CHANNELS] = {
+static const signed char channel_map_ds[HDSP_MAX_CHANNELS] = {
 	/* ADAT channels are remapped */
 	1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23,
 	/* channels 12 and 13 are S/PDIF */
@@ -526,7 +526,7 @@  static const char channel_map_ds[HDSP_MAX_CHANNELS] = {
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
 };
 
-static const char channel_map_H9632_ss[HDSP_MAX_CHANNELS] = {
+static const signed char channel_map_H9632_ss[HDSP_MAX_CHANNELS] = {
 	/* ADAT channels */
 	0, 1, 2, 3, 4, 5, 6, 7,
 	/* SPDIF */
@@ -540,7 +540,7 @@  static const char channel_map_H9632_ss[HDSP_MAX_CHANNELS] = {
 	-1, -1
 };
 
-static const char channel_map_H9632_ds[HDSP_MAX_CHANNELS] = {
+static const signed char channel_map_H9632_ds[HDSP_MAX_CHANNELS] = {
 	/* ADAT */
 	1, 3, 5, 7,
 	/* SPDIF */
@@ -554,7 +554,7 @@  static const char channel_map_H9632_ds[HDSP_MAX_CHANNELS] = {
 	-1, -1, -1, -1, -1, -1
 };
 
-static const char channel_map_H9632_qs[HDSP_MAX_CHANNELS] = {
+static const signed char channel_map_H9632_qs[HDSP_MAX_CHANNELS] = {
 	/* ADAT is disabled in this mode */
 	/* SPDIF */
 	8, 9,
@@ -3939,7 +3939,7 @@  static snd_pcm_uframes_t snd_hdsp_hw_pointer(struct snd_pcm_substream *substream
 	return hdsp_hw_pointer(hdsp);
 }
 
-static char *hdsp_channel_buffer_location(struct hdsp *hdsp,
+static signed char *hdsp_channel_buffer_location(struct hdsp *hdsp,
 					     int stream,
 					     int channel)
 
@@ -3964,7 +3964,7 @@  static int snd_hdsp_playback_copy(struct snd_pcm_substream *substream,
 				  void __user *src, unsigned long count)
 {
 	struct hdsp *hdsp = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	if (snd_BUG_ON(pos + count > HDSP_CHANNEL_BUFFER_BYTES))
 		return -EINVAL;
@@ -3982,7 +3982,7 @@  static int snd_hdsp_playback_copy_kernel(struct snd_pcm_substream *substream,
 					 void *src, unsigned long count)
 {
 	struct hdsp *hdsp = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = hdsp_channel_buffer_location(hdsp, substream->pstr->stream, channel);
 	if (snd_BUG_ON(!channel_buf))
@@ -3996,7 +3996,7 @@  static int snd_hdsp_capture_copy(struct snd_pcm_substream *substream,
 				 void __user *dst, unsigned long count)
 {
 	struct hdsp *hdsp = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	if (snd_BUG_ON(pos + count > HDSP_CHANNEL_BUFFER_BYTES))
 		return -EINVAL;
@@ -4014,7 +4014,7 @@  static int snd_hdsp_capture_copy_kernel(struct snd_pcm_substream *substream,
 					void *dst, unsigned long count)
 {
 	struct hdsp *hdsp = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = hdsp_channel_buffer_location(hdsp, substream->pstr->stream, channel);
 	if (snd_BUG_ON(!channel_buf))
@@ -4028,7 +4028,7 @@  static int snd_hdsp_hw_silence(struct snd_pcm_substream *substream,
 			       unsigned long count)
 {
 	struct hdsp *hdsp = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = hdsp_channel_buffer_location (hdsp, substream->pstr->stream, channel);
 	if (snd_BUG_ON(!channel_buf))
diff --git a/sound/pci/rme9652/rme9652.c b/sound/pci/rme9652/rme9652.c
index 1d614fe89a6a..e7c320afefe8 100644
--- a/sound/pci/rme9652/rme9652.c
+++ b/sound/pci/rme9652/rme9652.c
@@ -230,7 +230,7 @@  struct snd_rme9652 {
 	int last_spdif_sample_rate;	/* so that we can catch externally ... */
 	int last_adat_sample_rate;	/* ... induced rate changes            */
 
-	const char *channel_map;
+	const signed char *channel_map;
 
 	struct snd_card *card;
 	struct snd_pcm *pcm;
@@ -247,12 +247,12 @@  struct snd_rme9652 {
    where the data for that channel can be read/written from/to.
 */
 
-static const char channel_map_9652_ss[26] = {
+static const signed char channel_map_9652_ss[26] = {
 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
 	18, 19, 20, 21, 22, 23, 24, 25
 };
 
-static const char channel_map_9636_ss[26] = {
+static const signed char channel_map_9636_ss[26] = {
 	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 
 	/* channels 16 and 17 are S/PDIF */
 	24, 25,
@@ -260,7 +260,7 @@  static const char channel_map_9636_ss[26] = {
 	-1, -1, -1, -1, -1, -1, -1, -1
 };
 
-static const char channel_map_9652_ds[26] = {
+static const signed char channel_map_9652_ds[26] = {
 	/* ADAT channels are remapped */
 	1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23,
 	/* channels 12 and 13 are S/PDIF */
@@ -269,7 +269,7 @@  static const char channel_map_9652_ds[26] = {
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
 };
 
-static const char channel_map_9636_ds[26] = {
+static const signed char channel_map_9636_ds[26] = {
 	/* ADAT channels are remapped */
 	1, 3, 5, 7, 9, 11, 13, 15,
 	/* channels 8 and 9 are S/PDIF */
@@ -1819,7 +1819,7 @@  static snd_pcm_uframes_t snd_rme9652_hw_pointer(struct snd_pcm_substream *substr
 	return rme9652_hw_pointer(rme9652);
 }
 
-static char *rme9652_channel_buffer_location(struct snd_rme9652 *rme9652,
+static signed char *rme9652_channel_buffer_location(struct snd_rme9652 *rme9652,
 					     int stream,
 					     int channel)
 
@@ -1847,7 +1847,7 @@  static int snd_rme9652_playback_copy(struct snd_pcm_substream *substream,
 				     void __user *src, unsigned long count)
 {
 	struct snd_rme9652 *rme9652 = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	if (snd_BUG_ON(pos + count > RME9652_CHANNEL_BUFFER_BYTES))
 		return -EINVAL;
@@ -1867,7 +1867,7 @@  static int snd_rme9652_playback_copy_kernel(struct snd_pcm_substream *substream,
 					    void *src, unsigned long count)
 {
 	struct snd_rme9652 *rme9652 = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = rme9652_channel_buffer_location(rme9652,
 						      substream->pstr->stream,
@@ -1883,7 +1883,7 @@  static int snd_rme9652_capture_copy(struct snd_pcm_substream *substream,
 				    void __user *dst, unsigned long count)
 {
 	struct snd_rme9652 *rme9652 = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	if (snd_BUG_ON(pos + count > RME9652_CHANNEL_BUFFER_BYTES))
 		return -EINVAL;
@@ -1903,7 +1903,7 @@  static int snd_rme9652_capture_copy_kernel(struct snd_pcm_substream *substream,
 					   void *dst, unsigned long count)
 {
 	struct snd_rme9652 *rme9652 = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = rme9652_channel_buffer_location(rme9652,
 						      substream->pstr->stream,
@@ -1919,7 +1919,7 @@  static int snd_rme9652_hw_silence(struct snd_pcm_substream *substream,
 				  unsigned long count)
 {
 	struct snd_rme9652 *rme9652 = snd_pcm_substream_chip(substream);
-	char *channel_buf;
+	signed char *channel_buf;
 
 	channel_buf = rme9652_channel_buffer_location (rme9652,
 						       substream->pstr->stream,