ALSA: firewire-lib: Add some AV/C general commands

This commit adds three commands, which may be used by some firewire device
drivers. These commands are defined in 'AV/C Digital Interface Command Set
General Specification Version 4.2 (2004006, 1394TA)'.

1. PLUG INFO command (clause 10.1)
2. INPUT PLUG SIGNAL FORMAT command (clause 10.10)
3. OUTPUT PLUG SIGNAL FORMAT command (clause 10.11)

By the command 1, the drivers can get the number of plugs for AV/C unit or
subunit.
By the command 2 and 3, the drivers can get/set sampling frequency.

The 'firewire-speakers' already uses INPUT PLUG SIGNAL FORMAT command to set
sampling rate. So this commit also affects the driver.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/fcp.c

@@ -10,12 +10,14 @@
 #include <linux/firewire-constants.h>
 #include <linux/list.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/wait.h>
 #include <linux/delay.h>
 #include "fcp.h"
 #include "lib.h"
+#include "amdtp.h"
 
 #define CTS_AVC 0x00
 
@@ -23,6 +25,158 @@
 #define ERROR_DELAY_MS	5
 #define FCP_TIMEOUT_MS	125
 
+int avc_general_set_sig_fmt(struct fw_unit *unit, unsigned int rate,
+			    enum avc_general_plug_dir dir,
+			    unsigned short pid)
+{
+	unsigned int sfc;
+	u8 *buf;
+	bool flag;
+	int err;
+
+	flag = false;
+	for (sfc = 0; sfc < CIP_SFC_COUNT; sfc++) {
+		if (amdtp_rate_table[sfc] == rate) {
+			flag = true;
+			break;
+		}
+	}
+	if (!flag)
+		return -EINVAL;
+
+	buf = kzalloc(8, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf[0] = 0x00;		/* AV/C CONTROL */
+	buf[1] = 0xff;		/* UNIT */
+	if (dir == AVC_GENERAL_PLUG_DIR_IN)
+		buf[2] = 0x19;	/* INPUT PLUG SIGNAL FORMAT */
+	else
+		buf[2] = 0x18;	/* OUTPUT PLUG SIGNAL FORMAT */
+	buf[3] = 0xff & pid;	/* plug id */
+	buf[4] = 0x90;		/* EOH_1, Form_1, FMT. AM824 */
+	buf[5] = 0x07 & sfc;	/* FDF-hi. AM824, frequency */
+	buf[6] = 0xff;		/* FDF-mid. AM824, SYT hi (not used)*/
+	buf[7] = 0xff;		/* FDF-low. AM824, SYT lo (not used) */
+
+	/* do transaction and check buf[1-5] are the same against command */
+	err = fcp_avc_transaction(unit, buf, 8, buf, 8,
+				  BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5));
+	if (err >= 0 && err < 8)
+		err = -EIO;
+	else if (buf[0] == 0x08) /* NOT IMPLEMENTED */
+		err = -ENOSYS;
+	else if (buf[0] == 0x0a) /* REJECTED */
+		err = -EINVAL;
+	if (err < 0)
+		goto end;
+
+	err = 0;
+end:
+	kfree(buf);
+	return err;
+}
+EXPORT_SYMBOL(avc_general_set_sig_fmt);
+
+int avc_general_get_sig_fmt(struct fw_unit *unit, unsigned int *rate,
+			    enum avc_general_plug_dir dir,
+			    unsigned short pid)
+{
+	unsigned int sfc;
+	u8 *buf;
+	int err;
+
+	buf = kzalloc(8, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf[0] = 0x01;		/* AV/C STATUS */
+	buf[1] = 0xff;		/* Unit */
+	if (dir == AVC_GENERAL_PLUG_DIR_IN)
+		buf[2] = 0x19;	/* INPUT PLUG SIGNAL FORMAT */
+	else
+		buf[2] = 0x18;	/* OUTPUT PLUG SIGNAL FORMAT */
+	buf[3] = 0xff & pid;	/* plug id */
+	buf[4] = 0x90;		/* EOH_1, Form_1, FMT. AM824 */
+	buf[5] = 0xff;		/* FDF-hi. AM824, frequency */
+	buf[6] = 0xff;		/* FDF-mid. AM824, SYT hi (not used) */
+	buf[7] = 0xff;		/* FDF-low. AM824, SYT lo (not used) */
+
+	/* do transaction and check buf[1-4] are the same against command */
+	err = fcp_avc_transaction(unit, buf, 8, buf, 8,
+				  BIT(1) | BIT(2) | BIT(3) | BIT(4));
+	if (err >= 0 && err < 8)
+		err = -EIO;
+	else if (buf[0] == 0x08) /* NOT IMPLEMENTED */
+		err = -ENOSYS;
+	else if (buf[0] == 0x0a) /* REJECTED */
+		err = -EINVAL;
+	else if (buf[0] == 0x0b) /* IN TRANSITION */
+		err = -EAGAIN;
+	if (err < 0)
+		goto end;
+
+	/* check sfc field and pick up rate */
+	sfc = 0x07 & buf[5];
+	if (sfc >= CIP_SFC_COUNT) {
+		err = -EAGAIN;	/* also in transition */
+		goto end;
+	}
+
+	*rate = amdtp_rate_table[sfc];
+	err = 0;
+end:
+	kfree(buf);
+	return err;
+}
+EXPORT_SYMBOL(avc_general_get_sig_fmt);
+
+int avc_general_get_plug_info(struct fw_unit *unit, unsigned int subunit_type,
+			      unsigned int subunit_id, unsigned int subfunction,
+			      u8 info[AVC_PLUG_INFO_BUF_BYTES])
+{
+	u8 *buf;
+	int err;
+
+	/* extended subunit in spec.4.2 is not supported */
+	if ((subunit_type == 0x1E) || (subunit_id == 5))
+		return -EINVAL;
+
+	buf = kzalloc(8, GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf[0] = 0x01;	/* AV/C STATUS */
+	/* UNIT or Subunit, Functionblock */
+	buf[1] = ((subunit_type & 0x1f) << 3) | (subunit_id & 0x7);
+	buf[2] = 0x02;	/* PLUG INFO */
+	buf[3] = 0xff & subfunction;
+
+	err = fcp_avc_transaction(unit, buf, 8, buf, 8, BIT(1) | BIT(2));
+	if (err >= 0 && err < 8)
+		err = -EIO;
+	else if (buf[0] == 0x08) /* NOT IMPLEMENTED */
+		err = -ENOSYS;
+	else if (buf[0] == 0x0a) /* REJECTED */
+		err = -EINVAL;
+	else if (buf[0] == 0x0b) /* IN TRANSITION */
+		err = -EAGAIN;
+	if (err < 0)
+		goto end;
+
+	info[0] = buf[4];
+	info[1] = buf[5];
+	info[2] = buf[6];
+	info[3] = buf[7];
+
+	err = 0;
+end:
+	kfree(buf);
+	return err;
+}
+EXPORT_SYMBOL(avc_general_get_plug_info);
+
 static DEFINE_SPINLOCK(transactions_lock);
 static LIST_HEAD(transactions);