can: peak_pci: add support of some new PEAK-System PCI cards

This patch adds the support of some new PEAK-System PCI cards in the CAN
network sub-system. These are:

PCAN-PCIeC (PCI-ExpressCard)
PCAN-mminiPCI (mini-PCI)
PCAN-PCI (PCI next-gen)

This patch also adds the control of the blinking leds of the PCAN-PCIeC.

Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

2 files changed, 506 insertions, 17 deletions

diff --git a/drivers/net/can/sja1000/Kconfig b/drivers/net/can/sja1000/Kconfig
index b21523d..fdc3926 100644
--- a/drivers/net/can/sja1000/Kconfig
+++ b/drivers/net/can/sja1000/Kconfig
@@ -44,11 +44,23 @@ config CAN_EMS_PCI
 	  (http://www.ems-wuensche.de).
 
 config CAN_PEAK_PCI
-	tristate "PEAK PCAN PCI/PCIe Cards"
+	tristate "PEAK PCAN-PCI/PCIe/miniPCI Cards"
 	depends on PCI
 	---help---
-	  This driver is for the PCAN PCI/PCIe cards (1, 2, 3 or 4 channels)
-	  from PEAK Systems (http://www.peak-system.com).
+	  This driver is for the PCAN-PCI/PCIe/miniPCI cards
+	  (1, 2, 3 or 4 channels) from PEAK-System Technik
+	  (http://www.peak-system.com).
+
+config CAN_PEAK_PCIEC
+	bool "PEAK PCAN-ExpressCard Cards"
+	depends on CAN_PEAK_PCI
+	select I2C
+	select I2C_ALGOBIT
+	default y
+	---help---
+	  Say Y here if you want to use a PCAN-ExpressCard from PEAK-System
+	  Technik. This will also automatically select I2C and I2C_ALGO
+	  configuration options.
 
 config CAN_KVASER_PCI
 	tristate "Kvaser PCIcanx and Kvaser PCIcan PCI Cards"
diff --git a/drivers/net/can/sja1000/peak_pci.c b/drivers/net/can/sja1000/peak_pci.c
index 2147959..5f92b86 100644
--- a/drivers/net/can/sja1000/peak_pci.c
+++ b/drivers/net/can/sja1000/peak_pci.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
+ * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>
  *
  * Derived from the PCAN project file driver/src/pcan_pci.c:
  *
@@ -13,10 +14,6 @@
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
 #include <linux/kernel.h>
@@ -26,22 +23,26 @@
 #include <linux/delay.h>
 #include <linux/pci.h>
 #include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
 #include <linux/can.h>
 #include <linux/can/dev.h>
 
 #include "sja1000.h"
 
 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
-MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCI/PCIe cards");
-MODULE_SUPPORTED_DEVICE("PEAK PCAN PCI/PCIe CAN card");
+MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCI family cards");
+MODULE_SUPPORTED_DEVICE("PEAK PCAN PCI/PCIe/PCIeC miniPCI CAN cards");
 MODULE_LICENSE("GPL v2");
 
 #define DRV_NAME  "peak_pci"
 
+struct peak_pciec_card;
 struct peak_pci_chan {
 	void __iomem *cfg_base;		/* Common for all channels */
 	struct net_device *prev_dev;	/* Chain of network devices */
 	u16 icr_mask;			/* Interrupt mask for fast ack */
+	struct peak_pciec_card *pciec_card;	/* only for PCIeC LEDs */
 };
 
 #define PEAK_PCI_CAN_CLOCK	(16000000 / 2)
@@ -61,16 +62,464 @@ struct peak_pci_chan {
 
 #define PEAK_PCI_VENDOR_ID	0x001C	/* The PCI device and vendor IDs */
 #define PEAK_PCI_DEVICE_ID	0x0001	/* for PCI/PCIe slot cards */
+#define PEAK_PCIEC_DEVICE_ID	0x0002	/* for ExpressCard slot cards */
+#define PEAK_PCIE_DEVICE_ID	0x0003	/* for nextgen PCIe slot cards */
+#define PEAK_MPCI_DEVICE_ID	0x0008	/* The miniPCI slot cards */
+
+#define PEAK_PCI_CHAN_MAX	4
 
-static const u16 peak_pci_icr_masks[] = {0x02, 0x01, 0x40, 0x80};
+static const u16 peak_pci_icr_masks[PEAK_PCI_CHAN_MAX] = {
+	0x02, 0x01, 0x40, 0x80
+};
 
 static DEFINE_PCI_DEVICE_TABLE(peak_pci_tbl) = {
 	{PEAK_PCI_VENDOR_ID, PEAK_PCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
+	{PEAK_PCI_VENDOR_ID, PEAK_PCIE_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
+	{PEAK_PCI_VENDOR_ID, PEAK_MPCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
+#ifdef CONFIG_CAN_PEAK_PCIEC
+	{PEAK_PCI_VENDOR_ID, PEAK_PCIEC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
+#endif
 	{0,}
 };
 
 MODULE_DEVICE_TABLE(pci, peak_pci_tbl);
 
+#ifdef CONFIG_CAN_PEAK_PCIEC
+/*
+ * PCAN-ExpressCard needs I2C bit-banging configuration option.
+ */
+
+/* GPIOICR byte access offsets */
+#define PITA_GPOUT		0x18	/* GPx output value */
+#define PITA_GPIN		0x19	/* GPx input value */
+#define PITA_GPOEN		0x1A	/* configure GPx as ouput pin */
+
+/* I2C GP bits */
+#define PITA_GPIN_SCL		0x01	/* Serial Clock Line */
+#define PITA_GPIN_SDA		0x04	/* Serial DAta line */
+
+#define PCA9553_1_SLAVEADDR	(0xC4 >> 1)
+
+/* PCA9553 LS0 fields values */
+enum {
+	PCA9553_LOW,
+	PCA9553_HIGHZ,
+	PCA9553_PWM0,
+	PCA9553_PWM1
+};
+
+/* LEDs control */
+#define PCA9553_ON		PCA9553_LOW
+#define PCA9553_OFF		PCA9553_HIGHZ
+#define PCA9553_SLOW		PCA9553_PWM0
+#define PCA9553_FAST		PCA9553_PWM1
+
+#define PCA9553_LED(c)		(1 << (c))
+#define PCA9553_LED_STATE(s, c)	((s) << ((c) << 1))
+
+#define PCA9553_LED_ON(c)	PCA9553_LED_STATE(PCA9553_ON, c)
+#define PCA9553_LED_OFF(c)	PCA9553_LED_STATE(PCA9553_OFF, c)
+#define PCA9553_LED_SLOW(c)	PCA9553_LED_STATE(PCA9553_SLOW, c)
+#define PCA9553_LED_FAST(c)	PCA9553_LED_STATE(PCA9553_FAST, c)
+#define PCA9553_LED_MASK(c)	PCA9553_LED_STATE(0x03, c)
+
+#define PCA9553_LED_OFF_ALL	(PCA9553_LED_OFF(0) | PCA9553_LED_OFF(1))
+
+#define PCA9553_LS0_INIT	0x40 /* initial value (!= from 0x00) */
+
+struct peak_pciec_chan {
+	struct net_device *netdev;
+	unsigned long prev_rx_bytes;
+	unsigned long prev_tx_bytes;
+};
+
+struct peak_pciec_card {
+	void __iomem *cfg_base;		/* Common for all channels */
+	void __iomem *reg_base;		/* first channel base address */
+	u8 led_cache;			/* leds state cache */
+
+	/* PCIExpressCard i2c data */
+	struct i2c_algo_bit_data i2c_bit;
+	struct i2c_adapter led_chip;
+	struct delayed_work led_work;	/* led delayed work */
+	int chan_count;
+	struct peak_pciec_chan channel[PEAK_PCI_CHAN_MAX];
+};
+
+/* "normal" pci register write callback is overloaded for leds control */
+static void peak_pci_write_reg(const struct sja1000_priv *priv,
+			       int port, u8 val);
+
+static inline void pita_set_scl_highz(struct peak_pciec_card *card)
+{
+	u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SCL;
+	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
+}
+
+static inline void pita_set_sda_highz(struct peak_pciec_card *card)
+{
+	u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SDA;
+	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
+}
+
+static void peak_pciec_init_pita_gpio(struct peak_pciec_card *card)
+{
+	/* raise SCL & SDA GPIOs to high-Z */
+	pita_set_scl_highz(card);
+	pita_set_sda_highz(card);
+}
+
+static void pita_setsda(void *data, int state)
+{
+	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
+	u8 gp_out, gp_outen;
+
+	/* set output sda always to 0 */
+	gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SDA;
+	writeb(gp_out, card->cfg_base + PITA_GPOUT);
+
+	/* control output sda with GPOEN */
+	gp_outen = readb(card->cfg_base + PITA_GPOEN);
+	if (state)
+		gp_outen &= ~PITA_GPIN_SDA;
+	else
+		gp_outen |= PITA_GPIN_SDA;
+
+	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
+}
+
+static void pita_setscl(void *data, int state)
+{
+	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
+	u8 gp_out, gp_outen;
+
+	/* set output scl always to 0 */
+	gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SCL;
+	writeb(gp_out, card->cfg_base + PITA_GPOUT);
+
+	/* control output scl with GPOEN */
+	gp_outen = readb(card->cfg_base + PITA_GPOEN);
+	if (state)
+		gp_outen &= ~PITA_GPIN_SCL;
+	else
+		gp_outen |= PITA_GPIN_SCL;
+
+	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
+}
+
+static int pita_getsda(void *data)
+{
+	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
+
+	/* set tristate */
+	pita_set_sda_highz(card);
+
+	return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SDA) ? 1 : 0;
+}
+
+static int pita_getscl(void *data)
+{
+	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
+
+	/* set tristate */
+	pita_set_scl_highz(card);
+
+	return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SCL) ? 1 : 0;
+}
+
+/*
+ * write commands to the LED chip though the I2C-bus of the PCAN-PCIeC
+ */
+static int peak_pciec_write_pca9553(struct peak_pciec_card *card,
+				    u8 offset, u8 data)
+{
+	u8 buffer[2] = {
+		offset,
+		data
+	};
+	struct i2c_msg msg = {
+		.addr = PCA9553_1_SLAVEADDR,
+		.len = 2,
+		.buf = buffer,
+	};
+	int ret;
+
+	/* cache led mask */
+	if ((offset == 5) && (data == card->led_cache))
+		return 0;
+
+	ret = i2c_transfer(&card->led_chip, &msg, 1);
+	if (ret < 0)
+		return ret;
+
+	if (offset == 5)
+		card->led_cache = data;
+
+	return 0;
+}
+
+/*
+ * delayed work callback used to control the LEDs
+ */
+static void peak_pciec_led_work(struct work_struct *work)
+{
+	struct peak_pciec_card *card =
+		container_of(work, struct peak_pciec_card, led_work.work);
+	struct net_device *netdev;
+	u8 new_led = card->led_cache;
+	int i, up_count = 0;
+
+	/* first check what is to do */
+	for (i = 0; i < card->chan_count; i++) {
+		/* default is: not configured */
+		new_led &= ~PCA9553_LED_MASK(i);
+		new_led |= PCA9553_LED_ON(i);
+
+		netdev = card->channel[i].netdev;
+		if (!netdev || !(netdev->flags & IFF_UP))
+			continue;
+
+		up_count++;
+
+		/* no activity (but configured) */
+		new_led &= ~PCA9553_LED_MASK(i);
+		new_led |= PCA9553_LED_SLOW(i);
+
+		/* if bytes counters changed, set fast blinking led */
+		if (netdev->stats.rx_bytes != card->channel[i].prev_rx_bytes) {
+			card->channel[i].prev_rx_bytes = netdev->stats.rx_bytes;
+			new_led &= ~PCA9553_LED_MASK(i);
+			new_led |= PCA9553_LED_FAST(i);
+		}
+		if (netdev->stats.tx_bytes != card->channel[i].prev_tx_bytes) {
+			card->channel[i].prev_tx_bytes = netdev->stats.tx_bytes;
+			new_led &= ~PCA9553_LED_MASK(i);
+			new_led |= PCA9553_LED_FAST(i);
+		}
+	}
+
+	/* check if LS0 settings changed, only update i2c if so */
+	peak_pciec_write_pca9553(card, 5, new_led);
+
+	/* restart timer (except if no more configured channels) */
+	if (up_count)
+		schedule_delayed_work(&card->led_work, HZ);
+}
+
+/*
+ * set LEDs blinking state
+ */
+static void peak_pciec_set_leds(struct peak_pciec_card *card, u8 led_mask, u8 s)
+{
+	u8 new_led = card->led_cache;
+	int i;
+
+	/* first check what is to do */
+	for (i = 0; i < card->chan_count; i++)
+		if (led_mask & PCA9553_LED(i)) {
+			new_led &= ~PCA9553_LED_MASK(i);
+			new_led |= PCA9553_LED_STATE(s, i);
+		}
+
+	/* check if LS0 settings changed, only update i2c if so */
+	peak_pciec_write_pca9553(card, 5, new_led);
+}
+
+/*
+ * start one second delayed work to control LEDs
+ */
+static void peak_pciec_start_led_work(struct peak_pciec_card *card)
+{
+	if (!delayed_work_pending(&card->led_work))
+		schedule_delayed_work(&card->led_work, HZ);
+}
+
+/*
+ * stop LEDs delayed work
+ */
+static void peak_pciec_stop_led_work(struct peak_pciec_card *card)
+{
+	cancel_delayed_work_sync(&card->led_work);
+}
+
+/*
+ * initialize the PCA9553 4-bit I2C-bus LED chip
+ */
+static int peak_pciec_init_leds(struct peak_pciec_card *card)
+{
+	int err;
+
+	/* prescaler for frequency 0: "SLOW" = 1 Hz = "44" */
+	err = peak_pciec_write_pca9553(card, 1, 44 / 1);
+	if (err)
+		return err;
+
+	/* duty cycle 0: 50% */
+	err = peak_pciec_write_pca9553(card, 2, 0x80);
+	if (err)
+		return err;
+
+	/* prescaler for frequency 1: "FAST" = 5 Hz */
+	err = peak_pciec_write_pca9553(card, 3, 44 / 5);
+	if (err)
+		return err;
+
+	/* duty cycle 1: 50% */
+	err = peak_pciec_write_pca9553(card, 4, 0x80);
+	if (err)
+		return err;
+
+	/* switch LEDs to initial state */
+	return peak_pciec_write_pca9553(card, 5, PCA9553_LS0_INIT);
+}
+
+/*
+ * restore LEDs state to off peak_pciec_leds_exit
+ */
+static void peak_pciec_leds_exit(struct peak_pciec_card *card)
+{
+	/* switch LEDs to off */
+	peak_pciec_write_pca9553(card, 5, PCA9553_LED_OFF_ALL);
+}
+
+/*
+ * normal write sja1000 register method overloaded to catch when controller
+ * is started or stopped, to control leds
+ */
+static void peak_pciec_write_reg(const struct sja1000_priv *priv,
+				 int port, u8 val)
+{
+	struct peak_pci_chan *chan = priv->priv;
+	struct peak_pciec_card *card = chan->pciec_card;
+	int c = (priv->reg_base - card->reg_base) / PEAK_PCI_CHAN_SIZE;
+
+	/* sja1000 register changes control the leds state */
+	if (port == REG_MOD)
+		switch (val) {
+		case MOD_RM:
+			/* Reset Mode: set led on */
+			peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_ON);
+			break;
+		case 0x00:
+			/* Normal Mode: led slow blinking and start led timer */
+			peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_SLOW);
+			peak_pciec_start_led_work(card);
+			break;
+		default:
+			break;
+		}
+
+	/* call base function */
+	peak_pci_write_reg(priv, port, val);
+}
+
+static struct i2c_algo_bit_data peak_pciec_i2c_bit_ops = {
+	.setsda	= pita_setsda,
+	.setscl	= pita_setscl,
+	.getsda	= pita_getsda,
+	.getscl	= pita_getscl,
+	.udelay	= 10,
+	.timeout = HZ,
+};
+
+static int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
+{
+	struct sja1000_priv *priv = netdev_priv(dev);
+	struct peak_pci_chan *chan = priv->priv;
+	struct peak_pciec_card *card;
+	int err;
+
+	/* copy i2c object address from 1st channel */
+	if (chan->prev_dev) {
+		struct sja1000_priv *prev_priv = netdev_priv(chan->prev_dev);
+		struct peak_pci_chan *prev_chan = prev_priv->priv;
+
+		card = prev_chan->pciec_card;
+		if (!card)
+			return -ENODEV;
+
+	/* channel is the first one: do the init part */
+	} else {
+		/* create the bit banging I2C adapter structure */
+		card = kzalloc(sizeof(struct peak_pciec_card), GFP_KERNEL);
+		if (!card) {
+			dev_err(&pdev->dev,
+				 "failed allocating memory for i2c chip\n");
+			return -ENOMEM;
+		}
+
+		card->cfg_base = chan->cfg_base;
+		card->reg_base = priv->reg_base;
+
+		card->led_chip.owner = THIS_MODULE;
+		card->led_chip.dev.parent = &pdev->dev;
+		card->led_chip.algo_data = &card->i2c_bit;
+		strncpy(card->led_chip.name, "peak_i2c",
+			sizeof(card->led_chip.name));
+
+		card->i2c_bit = peak_pciec_i2c_bit_ops;
+		card->i2c_bit.udelay = 10;
+		card->i2c_bit.timeout = HZ;
+		card->i2c_bit.data = card;
+
+		peak_pciec_init_pita_gpio(card);
+
+		err = i2c_bit_add_bus(&card->led_chip);
+		if (err) {
+			dev_err(&pdev->dev, "i2c init failed\n");
+			goto pciec_init_err_1;
+		}
+
+		err = peak_pciec_init_leds(card);
+		if (err) {
+			dev_err(&pdev->dev, "leds hardware init failed\n");
+			goto pciec_init_err_2;
+		}
+
+		INIT_DELAYED_WORK(&card->led_work, peak_pciec_led_work);
+		/* PCAN-ExpressCard needs its own callback for leds */
+		priv->write_reg = peak_pciec_write_reg;
+	}
+
+	chan->pciec_card = card;
+	card->channel[card->chan_count++].netdev = dev;
+
+	return 0;
+
+pciec_init_err_2:
+	i2c_del_adapter(&card->led_chip);
+
+pciec_init_err_1:
+	peak_pciec_init_pita_gpio(card);
+	kfree(card);
+
+	return err;
+}
+
+static void peak_pciec_remove(struct peak_pciec_card *card)
+{
+	peak_pciec_stop_led_work(card);
+	peak_pciec_leds_exit(card);
+	i2c_del_adapter(&card->led_chip);
+	peak_pciec_init_pita_gpio(card);
+	kfree(card);
+}
+
+#else /* CONFIG_CAN_PEAK_PCIEC */
+
+/*
+ * Placebo functions when PCAN-ExpressCard support is not selected
+ */
+static inline int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
+{
+	return -ENODEV;
+}
+
+static inline void peak_pciec_remove(struct peak_pciec_card *card)
+{
+}
+#endif /* CONFIG_CAN_PEAK_PCIEC */
+
 static u8 peak_pci_read_reg(const struct sja1000_priv *priv, int port)
 {
 	return readb(priv->reg_base + (port << 2));
@@ -188,17 +637,31 @@ static int __devinit peak_pci_probe(struct pci_dev *pdev,
 
 		SET_NETDEV_DEV(dev, &pdev->dev);
 
+		/* Create chain of SJA1000 devices */
+		chan->prev_dev = pci_get_drvdata(pdev);
+		pci_set_drvdata(pdev, dev);
+
+		/*
+		 * PCAN-ExpressCard needs some additional i2c init.
+		 * This must be done *before* register_sja1000dev() but
+		 * *after* devices linkage
+		 */
+		if (pdev->device == PEAK_PCIEC_DEVICE_ID) {
+			err = peak_pciec_probe(pdev, dev);
+			if (err) {
+				dev_err(&pdev->dev,
+					"failed to probe device (err %d)\n",
+					err);
+				goto failure_free_dev;
+			}
+		}
+
 		err = register_sja1000dev(dev);
 		if (err) {
 			dev_err(&pdev->dev, "failed to register device\n");
-			free_sja1000dev(dev);
-			goto failure_remove_channels;
+			goto failure_free_dev;
 		}
 
-		/* Create chain of SJA1000 devices */
-		chan->prev_dev = pci_get_drvdata(pdev);
-		pci_set_drvdata(pdev, dev);
-
 		dev_info(&pdev->dev,
 			 "%s at reg_base=0x%p cfg_base=0x%p irq=%d\n",
 			 dev->name, priv->reg_base, chan->cfg_base, dev->irq);
@@ -209,10 +672,15 @@ static int __devinit peak_pci_probe(struct pci_dev *pdev,
 
 	return 0;
 
+failure_free_dev:
+	pci_set_drvdata(pdev, chan->prev_dev);
+	free_sja1000dev(dev);
+
 failure_remove_channels:
 	/* Disable interrupts */
 	writew(0x0, cfg_base + PITA_ICR + 2);
 
+	chan = NULL;
 	for (dev = pci_get_drvdata(pdev); dev; dev = chan->prev_dev) {
 		unregister_sja1000dev(dev);
 		free_sja1000dev(dev);
@@ -220,6 +688,10 @@ failure_remove_channels:
 		chan = priv->priv;
 	}
 
+	/* free any PCIeC resources too */
+	if (chan && chan->pciec_card)
+		peak_pciec_remove(chan->pciec_card);
+
 	pci_iounmap(pdev, reg_base);
 
 failure_unmap_cfg_base:
@@ -251,8 +723,13 @@ static void __devexit peak_pci_remove(struct pci_dev *pdev)
 		unregister_sja1000dev(dev);
 		free_sja1000dev(dev);
 		dev = chan->prev_dev;
-		if (!dev)
+
+		if (!dev) {
+			/* do that only for first channel */
+			if (chan->pciec_card)
+				peak_pciec_remove(chan->pciec_card);
 			break;
+		}
 		priv = netdev_priv(dev);
 		chan = priv->priv;
 	}