drivers/ieee802154: add support for the at86rf230/231 transceivers

The AT86RF231 is a feature rich, low-power 2.4 GHz radio transceiver
designed for industrial and consumer ZigBee/IEEE 802.15.4, 6LoWPAN,
RF4CE and high data rate 2.4 GHz ISM band applications.

This patch adds support for the Atmel RF230/231 radio transceivers.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ieee802154/Kconfig

@@ -19,6 +19,7 @@ config IEEE802154_FAKEHARD
 
           This driver can also be built as a module. To do so say M here.
 	  The module will be called 'fakehard'.
+
 config IEEE802154_FAKELB
 	depends on IEEE802154_DRIVERS && MAC802154
 	tristate "IEEE 802.15.4 loopback driver"
@@ -28,3 +29,8 @@ config IEEE802154_FAKELB
 
 	  This driver can also be built as a module. To do so say M here.
 	  The module will be called 'fakelb'.
+
+config IEEE802154_AT86RF230
+        depends on IEEE802154_DRIVERS && MAC802154
+        tristate "AT86RF230/231 transceiver driver"
+        depends on SPI

drivers/ieee802154/Makefile

 obj-$(CONFIG_IEEE802154_FAKEHARD) += fakehard.o
 obj-$(CONFIG_IEEE802154_FAKELB) += fakelb.o
+obj-$(CONFIG_IEEE802154_AT86RF230) += at86rf230.o

drivers/ieee802154/at86rf230.c

+/*
+ * AT86RF230/RF231 driver
+ *
+ * Copyright (C) 2009-2012 Siemens AG
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Written by:
+ * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
+ * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/spinlock.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/at86rf230.h>
+#include <linux/skbuff.h>
+
+#include <net/mac802154.h>
+#include <net/wpan-phy.h>
+
+struct at86rf230_local {
+	struct spi_device *spi;
+	int rstn, slp_tr, dig2;
+
+	u8 part;
+	u8 vers;
+
+	u8 buf[2];
+	struct mutex bmux;
+
+	struct work_struct irqwork;
+	struct completion tx_complete;
+
+	struct ieee802154_dev *dev;
+
+	spinlock_t lock;
+	bool irq_disabled;
+	bool is_tx;
+};
+
+#define	RG_TRX_STATUS	(0x01)
+#define	SR_TRX_STATUS		0x01, 0x1f, 0
+#define	SR_RESERVED_01_3	0x01, 0x20, 5
+#define	SR_CCA_STATUS		0x01, 0x40, 6
+#define	SR_CCA_DONE		0x01, 0x80, 7
+#define	RG_TRX_STATE	(0x02)
+#define	SR_TRX_CMD		0x02, 0x1f, 0
+#define	SR_TRAC_STATUS		0x02, 0xe0, 5
+#define	RG_TRX_CTRL_0	(0x03)
+#define	SR_CLKM_CTRL		0x03, 0x07, 0
+#define	SR_CLKM_SHA_SEL		0x03, 0x08, 3
+#define	SR_PAD_IO_CLKM		0x03, 0x30, 4
+#define	SR_PAD_IO		0x03, 0xc0, 6
+#define	RG_TRX_CTRL_1	(0x04)
+#define	SR_IRQ_POLARITY		0x04, 0x01, 0
+#define	SR_IRQ_MASK_MODE	0x04, 0x02, 1
+#define	SR_SPI_CMD_MODE		0x04, 0x0c, 2
+#define	SR_RX_BL_CTRL		0x04, 0x10, 4
+#define	SR_TX_AUTO_CRC_ON	0x04, 0x20, 5
+#define	SR_IRQ_2_EXT_EN		0x04, 0x40, 6
+#define	SR_PA_EXT_EN		0x04, 0x80, 7
+#define	RG_PHY_TX_PWR	(0x05)
+#define	SR_TX_PWR		0x05, 0x0f, 0
+#define	SR_PA_LT		0x05, 0x30, 4
+#define	SR_PA_BUF_LT		0x05, 0xc0, 6
+#define	RG_PHY_RSSI	(0x06)
+#define	SR_RSSI			0x06, 0x1f, 0
+#define	SR_RND_VALUE		0x06, 0x60, 5
+#define	SR_RX_CRC_VALID		0x06, 0x80, 7
+#define	RG_PHY_ED_LEVEL	(0x07)
+#define	SR_ED_LEVEL		0x07, 0xff, 0
+#define	RG_PHY_CC_CCA	(0x08)
+#define	SR_CHANNEL		0x08, 0x1f, 0
+#define	SR_CCA_MODE		0x08, 0x60, 5
+#define	SR_CCA_REQUEST		0x08, 0x80, 7
+#define	RG_CCA_THRES	(0x09)
+#define	SR_CCA_ED_THRES		0x09, 0x0f, 0
+#define	SR_RESERVED_09_1	0x09, 0xf0, 4
+#define	RG_RX_CTRL	(0x0a)
+#define	SR_PDT_THRES		0x0a, 0x0f, 0
+#define	SR_RESERVED_0a_1	0x0a, 0xf0, 4
+#define	RG_SFD_VALUE	(0x0b)
+#define	SR_SFD_VALUE		0x0b, 0xff, 0
+#define	RG_TRX_CTRL_2	(0x0c)
+#define	SR_OQPSK_DATA_RATE	0x0c, 0x03, 0
+#define	SR_RESERVED_0c_2	0x0c, 0x7c, 2
+#define	SR_RX_SAFE_MODE		0x0c, 0x80, 7
+#define	RG_ANT_DIV	(0x0d)
+#define	SR_ANT_CTRL		0x0d, 0x03, 0
+#define	SR_ANT_EXT_SW_EN	0x0d, 0x04, 2
+#define	SR_ANT_DIV_EN		0x0d, 0x08, 3
+#define	SR_RESERVED_0d_2	0x0d, 0x70, 4
+#define	SR_ANT_SEL		0x0d, 0x80, 7
+#define	RG_IRQ_MASK	(0x0e)
+#define	SR_IRQ_MASK		0x0e, 0xff, 0
+#define	RG_IRQ_STATUS	(0x0f)
+#define	SR_IRQ_0_PLL_LOCK	0x0f, 0x01, 0
+#define	SR_IRQ_1_PLL_UNLOCK	0x0f, 0x02, 1
+#define	SR_IRQ_2_RX_START	0x0f, 0x04, 2
+#define	SR_IRQ_3_TRX_END	0x0f, 0x08, 3
+#define	SR_IRQ_4_CCA_ED_DONE	0x0f, 0x10, 4
+#define	SR_IRQ_5_AMI		0x0f, 0x20, 5
+#define	SR_IRQ_6_TRX_UR		0x0f, 0x40, 6
+#define	SR_IRQ_7_BAT_LOW	0x0f, 0x80, 7
+#define	RG_VREG_CTRL	(0x10)
+#define	SR_RESERVED_10_6	0x10, 0x03, 0
+#define	SR_DVDD_OK		0x10, 0x04, 2
+#define	SR_DVREG_EXT		0x10, 0x08, 3
+#define	SR_RESERVED_10_3	0x10, 0x30, 4
+#define	SR_AVDD_OK		0x10, 0x40, 6
+#define	SR_AVREG_EXT		0x10, 0x80, 7
+#define	RG_BATMON	(0x11)
+#define	SR_BATMON_VTH		0x11, 0x0f, 0
+#define	SR_BATMON_HR		0x11, 0x10, 4
+#define	SR_BATMON_OK		0x11, 0x20, 5
+#define	SR_RESERVED_11_1	0x11, 0xc0, 6
+#define	RG_XOSC_CTRL	(0x12)
+#define	SR_XTAL_TRIM		0x12, 0x0f, 0
+#define	SR_XTAL_MODE		0x12, 0xf0, 4
+#define	RG_RX_SYN	(0x15)
+#define	SR_RX_PDT_LEVEL		0x15, 0x0f, 0
+#define	SR_RESERVED_15_2	0x15, 0x70, 4
+#define	SR_RX_PDT_DIS		0x15, 0x80, 7
+#define	RG_XAH_CTRL_1	(0x17)
+#define	SR_RESERVED_17_8	0x17, 0x01, 0
+#define	SR_AACK_PROM_MODE	0x17, 0x02, 1
+#define	SR_AACK_ACK_TIME	0x17, 0x04, 2
+#define	SR_RESERVED_17_5	0x17, 0x08, 3
+#define	SR_AACK_UPLD_RES_FT	0x17, 0x10, 4
+#define	SR_AACK_FLTR_RES_FT	0x17, 0x20, 5
+#define	SR_RESERVED_17_2	0x17, 0x40, 6
+#define	SR_RESERVED_17_1	0x17, 0x80, 7
+#define	RG_FTN_CTRL	(0x18)
+#define	SR_RESERVED_18_2	0x18, 0x7f, 0
+#define	SR_FTN_START		0x18, 0x80, 7
+#define	RG_PLL_CF	(0x1a)
+#define	SR_RESERVED_1a_2	0x1a, 0x7f, 0
+#define	SR_PLL_CF_START		0x1a, 0x80, 7
+#define	RG_PLL_DCU	(0x1b)
+#define	SR_RESERVED_1b_3	0x1b, 0x3f, 0
+#define	SR_RESERVED_1b_2	0x1b, 0x40, 6
+#define	SR_PLL_DCU_START	0x1b, 0x80, 7
+#define	RG_PART_NUM	(0x1c)
+#define	SR_PART_NUM		0x1c, 0xff, 0
+#define	RG_VERSION_NUM	(0x1d)
+#define	SR_VERSION_NUM		0x1d, 0xff, 0
+#define	RG_MAN_ID_0	(0x1e)
+#define	SR_MAN_ID_0		0x1e, 0xff, 0
+#define	RG_MAN_ID_1	(0x1f)
+#define	SR_MAN_ID_1		0x1f, 0xff, 0
+#define	RG_SHORT_ADDR_0	(0x20)
+#define	SR_SHORT_ADDR_0		0x20, 0xff, 0
+#define	RG_SHORT_ADDR_1	(0x21)
+#define	SR_SHORT_ADDR_1		0x21, 0xff, 0
+#define	RG_PAN_ID_0	(0x22)
+#define	SR_PAN_ID_0		0x22, 0xff, 0
+#define	RG_PAN_ID_1	(0x23)
+#define	SR_PAN_ID_1		0x23, 0xff, 0
+#define	RG_IEEE_ADDR_0	(0x24)
+#define	SR_IEEE_ADDR_0		0x24, 0xff, 0
+#define	RG_IEEE_ADDR_1	(0x25)
+#define	SR_IEEE_ADDR_1		0x25, 0xff, 0
+#define	RG_IEEE_ADDR_2	(0x26)
+#define	SR_IEEE_ADDR_2		0x26, 0xff, 0
+#define	RG_IEEE_ADDR_3	(0x27)
+#define	SR_IEEE_ADDR_3		0x27, 0xff, 0
+#define	RG_IEEE_ADDR_4	(0x28)
+#define	SR_IEEE_ADDR_4		0x28, 0xff, 0
+#define	RG_IEEE_ADDR_5	(0x29)
+#define	SR_IEEE_ADDR_5		0x29, 0xff, 0
+#define	RG_IEEE_ADDR_6	(0x2a)
+#define	SR_IEEE_ADDR_6		0x2a, 0xff, 0
+#define	RG_IEEE_ADDR_7	(0x2b)
+#define	SR_IEEE_ADDR_7		0x2b, 0xff, 0
+#define	RG_XAH_CTRL_0	(0x2c)
+#define	SR_SLOTTED_OPERATION	0x2c, 0x01, 0
+#define	SR_MAX_CSMA_RETRIES	0x2c, 0x0e, 1
+#define	SR_MAX_FRAME_RETRIES	0x2c, 0xf0, 4
+#define	RG_CSMA_SEED_0	(0x2d)
+#define	SR_CSMA_SEED_0		0x2d, 0xff, 0
+#define	RG_CSMA_SEED_1	(0x2e)
+#define	SR_CSMA_SEED_1		0x2e, 0x07, 0
+#define	SR_AACK_I_AM_COORD	0x2e, 0x08, 3
+#define	SR_AACK_DIS_ACK		0x2e, 0x10, 4
+#define	SR_AACK_SET_PD		0x2e, 0x20, 5
+#define	SR_AACK_FVN_MODE	0x2e, 0xc0, 6
+#define	RG_CSMA_BE	(0x2f)
+#define	SR_MIN_BE		0x2f, 0x0f, 0
+#define	SR_MAX_BE		0x2f, 0xf0, 4
+
+#define CMD_REG		0x80
+#define CMD_REG_MASK	0x3f
+#define CMD_WRITE	0x40
+#define CMD_FB		0x20
+
+#define IRQ_BAT_LOW	(1 << 7)
+#define IRQ_TRX_UR	(1 << 6)
+#define IRQ_AMI		(1 << 5)
+#define IRQ_CCA_ED	(1 << 4)
+#define IRQ_TRX_END	(1 << 3)
+#define IRQ_RX_START	(1 << 2)
+#define IRQ_PLL_UNL	(1 << 1)
+#define IRQ_PLL_LOCK	(1 << 0)
+
+#define STATE_P_ON		0x00	/* BUSY */
+#define STATE_BUSY_RX		0x01
+#define STATE_BUSY_TX		0x02
+#define STATE_FORCE_TRX_OFF	0x03
+#define STATE_FORCE_TX_ON	0x04	/* IDLE */
+/* 0x05 */				/* INVALID_PARAMETER */
+#define STATE_RX_ON		0x06
+/* 0x07 */				/* SUCCESS */
+#define STATE_TRX_OFF		0x08
+#define STATE_TX_ON		0x09
+/* 0x0a - 0x0e */			/* 0x0a - UNSUPPORTED_ATTRIBUTE */
+#define STATE_SLEEP		0x0F
+#define STATE_BUSY_RX_AACK	0x11
+#define STATE_BUSY_TX_ARET	0x12
+#define STATE_BUSY_RX_AACK_ON	0x16
+#define STATE_BUSY_TX_ARET_ON	0x19
+#define STATE_RX_ON_NOCLK	0x1C
+#define STATE_RX_AACK_ON_NOCLK	0x1D
+#define STATE_BUSY_RX_AACK_NOCLK 0x1E
+#define STATE_TRANSITION_IN_PROGRESS 0x1F
+
+static int
+__at86rf230_write(struct at86rf230_local *lp, u8 addr, u8 data)
+{
+	u8 *buf = lp->buf;
+	int status;
+	struct spi_message msg;
+	struct spi_transfer xfer = {
+		.len	= 2,
+		.tx_buf	= buf,
+	};
+
+	buf[0] = (addr & CMD_REG_MASK) | CMD_REG | CMD_WRITE;
+	buf[1] = data;
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+
+	status = spi_sync(lp->spi, &msg);
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	if (msg.status)
+		status = msg.status;
+
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+
+	return status;
+}
+
+static int
+__at86rf230_read_subreg(struct at86rf230_local *lp,
+			u8 addr, u8 mask, int shift, u8 *data)
+{
+	u8 *buf = lp->buf;
+	int status;
+	struct spi_message msg;
+	struct spi_transfer xfer = {
+		.len	= 2,
+		.tx_buf	= buf,
+		.rx_buf	= buf,
+	};
+
+	buf[0] = (addr & CMD_REG_MASK) | CMD_REG;
+	buf[1] = 0xff;
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+
+	status = spi_sync(lp->spi, &msg);
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	if (msg.status)
+		status = msg.status;
+
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+
+	if (status == 0)
+		*data = buf[1];
+
+	return status;
+}
+
+static int
+at86rf230_read_subreg(struct at86rf230_local *lp,
+		      u8 addr, u8 mask, int shift, u8 *data)
+{
+	int status;
+
+	mutex_lock(&lp->bmux);
+	status = __at86rf230_read_subreg(lp, addr, mask, shift, data);
+	mutex_unlock(&lp->bmux);
+
+	return status;
+}
+
+static int
+at86rf230_write_subreg(struct at86rf230_local *lp,
+		       u8 addr, u8 mask, int shift, u8 data)
+{
+	int status;
+	u8 val;
+
+	mutex_lock(&lp->bmux);
+	status = __at86rf230_read_subreg(lp, addr, 0xff, 0, &val);
+	if (status)
+		goto out;
+
+	val &= ~mask;
+	val |= (data << shift) & mask;
+
+	status = __at86rf230_write(lp, addr, val);
+out:
+	mutex_unlock(&lp->bmux);
+
+	return status;
+}
+
+static int
+at86rf230_write_fbuf(struct at86rf230_local *lp, u8 *data, u8 len)
+{
+	u8 *buf = lp->buf;
+	int status;
+	struct spi_message msg;
+	struct spi_transfer xfer_head = {
+		.len		= 2,
+		.tx_buf		= buf,
+
+	};
+	struct spi_transfer xfer_buf = {
+		.len		= len,
+		.tx_buf		= data,
+	};
+
+	mutex_lock(&lp->bmux);
+	buf[0] = CMD_WRITE | CMD_FB;
+	buf[1] = len + 2; /* 2 bytes for CRC that isn't written */
+
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer_head, &msg);
+	spi_message_add_tail(&xfer_buf, &msg);
+
+	status = spi_sync(lp->spi, &msg);
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	if (msg.status)
+		status = msg.status;
+
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+
+	mutex_unlock(&lp->bmux);
+	return status;
+}
+
+static int
+at86rf230_read_fbuf(struct at86rf230_local *lp, u8 *data, u8 *len, u8 *lqi)
+{
+	u8 *buf = lp->buf;
+	int status;
+	struct spi_message msg;
+	struct spi_transfer xfer_head = {
+		.len		= 2,
+		.tx_buf		= buf,
+		.rx_buf		= buf,
+	};
+	struct spi_transfer xfer_head1 = {
+		.len		= 2,
+		.tx_buf		= buf,
+		.rx_buf		= buf,
+	};
+	struct spi_transfer xfer_buf = {
+		.len		= 0,
+		.rx_buf		= data,
+	};
+
+	mutex_lock(&lp->bmux);
+
+	buf[0] = CMD_FB;
+	buf[1] = 0x00;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer_head, &msg);
+
+	status = spi_sync(lp->spi, &msg);
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+
+	xfer_buf.len = *(buf + 1) + 1;
+	*len = buf[1];
+
+	buf[0] = CMD_FB;
+	buf[1] = 0x00;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer_head1, &msg);
+	spi_message_add_tail(&xfer_buf, &msg);
+
+	status = spi_sync(lp->spi, &msg);
+
+	if (msg.status)
+		status = msg.status;
+
+	dev_vdbg(&lp->spi->dev, "status = %d\n", status);
+	dev_vdbg(&lp->spi->dev, "buf[0] = %02x\n", buf[0]);
+	dev_vdbg(&lp->spi->dev, "buf[1] = %02x\n", buf[1]);
+
+	if (status) {
+		if (lqi && (*len > lp->buf[1]))
+			*lqi = data[lp->buf[1]];
+	}
+	mutex_unlock(&lp->bmux);
+
+	return status;
+}
+
+static int
+at86rf230_ed(struct ieee802154_dev *dev, u8 *level)
+{
+	might_sleep();
+	BUG_ON(!level);
+	*level = 0xbe;
+	return 0;
+}
+
+static int
+at86rf230_state(struct ieee802154_dev *dev, int state)
+{
+	struct at86rf230_local *lp = dev->priv;
+	int rc;
+	u8 val;
+	u8 desired_status;
+
+	might_sleep();
+
+	if (state == STATE_FORCE_TX_ON)
+		desired_status = STATE_TX_ON;
+	else if (state == STATE_FORCE_TRX_OFF)
+		desired_status = STATE_TRX_OFF;
+	else
+		desired_status = state;
+
+	do {
+		rc = at86rf230_read_subreg(lp, SR_TRX_STATUS, &val);
+		if (rc)
+			goto err;
+	} while (val == STATE_TRANSITION_IN_PROGRESS);
+
+	if (val == desired_status)
+		return 0;
+
+	/* state is equal to phy states */
+	rc = at86rf230_write_subreg(lp, SR_TRX_CMD, state);
+	if (rc)
+		goto err;
+
+	do {
+		rc = at86rf230_read_subreg(lp, SR_TRX_STATUS, &val);
+		if (rc)
+			goto err;
+	} while (val == STATE_TRANSITION_IN_PROGRESS);
+
+
+	if (val == desired_status)
+		return 0;
+
+	pr_err("unexpected state change: %d, asked for %d\n", val, state);
+	return -EBUSY;
+
+err:
+	pr_err("error: %d\n", rc);
+	return rc;
+}
+
+static int
+at86rf230_start(struct ieee802154_dev *dev)
+{
+	struct at86rf230_local *lp = dev->priv;
+	u8 rc;
+
+	rc = at86rf230_write_subreg(lp, SR_RX_SAFE_MODE, 1);
+	if (rc)
+		return rc;
+
+	return at86rf230_state(dev, STATE_RX_ON);
+}
+
+static void
+at86rf230_stop(struct ieee802154_dev *dev)
+{
+	at86rf230_state(dev, STATE_FORCE_TRX_OFF);
+}
+
+static int
+at86rf230_channel(struct ieee802154_dev *dev, int page, int channel)
+{
+	struct at86rf230_local *lp = dev->priv;
+	int rc;
+
+	might_sleep();
+
+	if (page != 0 || channel < 11 || channel > 26) {
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
+	rc = at86rf230_write_subreg(lp, SR_CHANNEL, channel);
+	msleep(1); /* Wait for PLL */
+	dev->phy->current_channel = channel;
+
+	return 0;
+}
+
+static int
+at86rf230_xmit(struct ieee802154_dev *dev, struct sk_buff *skb)
+{
+	struct at86rf230_local *lp = dev->priv;
+	int rc;
+	unsigned long flags;
+
+	might_sleep();
+
+	rc = at86rf230_state(dev, STATE_FORCE_TX_ON);
+	if (rc)
+		goto err;
+
+	spin_lock_irqsave(&lp->lock, flags);
+	lp->is_tx = 1;
+	INIT_COMPLETION(lp->tx_complete);
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	rc = at86rf230_write_fbuf(lp, skb->data, skb->len);
+	if (rc)
+		goto err_rx;
+
+	rc = at86rf230_write_subreg(lp, SR_TRX_CMD, STATE_BUSY_TX);
+	if (rc)
+		goto err_rx;
+
+	rc = wait_for_completion_interruptible(&lp->tx_complete);
+	if (rc < 0)
+		goto err_rx;
+
+	rc = at86rf230_start(dev);
+
+	return rc;
+
+err_rx:
+	at86rf230_start(dev);
+err:
+	pr_err("error: %d\n", rc);
+
+	spin_lock_irqsave(&lp->lock, flags);
+	lp->is_tx = 0;
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	return rc;
+}
+
+static int at86rf230_rx(struct at86rf230_local *lp)
+{
+	u8 len = 128, lqi = 0;
+	int rc;
+	struct sk_buff *skb;
+
+	skb = alloc_skb(len, GFP_KERNEL);
+
+	if (!skb)
+		return -ENOMEM;
+
+	if (at86rf230_write_subreg(lp, SR_RX_PDT_DIS, 1) ||
+	    at86rf230_read_fbuf(lp, skb_put(skb, len), &len, &lqi) ||
+	    at86rf230_write_subreg(lp, SR_RX_SAFE_MODE, 1) ||
+	    at86rf230_write_subreg(lp, SR_RX_PDT_DIS, 0)) {
+		goto err;
+	}
+
+	if (len < 2)
+		goto err;
+
+	skb_trim(skb, len - 2); /* We do not put CRC into the frame */
+
+	ieee802154_rx_irqsafe(lp->dev, skb, lqi);
+
+	dev_dbg(&lp->spi->dev, "READ_FBUF: %d %d %x\n", rc, len, lqi);
+
+	return 0;
+err:
+	pr_debug("received frame is too small\n");
+
+	kfree_skb(skb);
+	return -EINVAL;
+}
+
+static struct ieee802154_ops at86rf230_ops = {
+	.owner = THIS_MODULE,
+	.xmit = at86rf230_xmit,
+	.ed = at86rf230_ed,
+	.set_channel = at86rf230_channel,
+	.start = at86rf230_start,
+	.stop = at86rf230_stop,
+};
+
+static void at86rf230_irqwork(struct work_struct *work)
+{
+	struct at86rf230_local *lp =
+		container_of(work, struct at86rf230_local, irqwork);
+	u8 status = 0, val;
+	int rc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&lp->lock, flags);
+	rc = at86rf230_read_subreg(lp, RG_IRQ_STATUS, 0xff, 0, &val);
+	status |= val;
+
+	status &= ~IRQ_PLL_LOCK; /* ignore */
+	status &= ~IRQ_RX_START; /* ignore */
+	status &= ~IRQ_AMI; /* ignore */
+	status &= ~IRQ_TRX_UR; /* FIXME: possibly handle ???*/
+
+	if (status & IRQ_TRX_END) {
+		status &= ~IRQ_TRX_END;
+		if (lp->is_tx) {
+			lp->is_tx = 0;
+			complete(&lp->tx_complete);
+		} else {
+			at86rf230_rx(lp);
+		}
+	}
+
+	if (lp->irq_disabled) {
+		lp->irq_disabled = 0;
+		enable_irq(lp->spi->irq);
+	}
+	spin_unlock_irqrestore(&lp->lock, flags);
+}
+
+static irqreturn_t at86rf230_isr(int irq, void *data)
+{
+	struct at86rf230_local *lp = data;
+
+	spin_lock(&lp->lock);
+	if (!lp->irq_disabled) {
+		disable_irq_nosync(irq);
+		lp->irq_disabled = 1;
+	}
+	spin_unlock(&lp->lock);
+
+	schedule_work(&lp->irqwork);
+
+	return IRQ_HANDLED;
+}
+
+
+static int at86rf230_hw_init(struct at86rf230_local *lp)
+{
+	u8 status;
+	int rc;
+
+	rc = at86rf230_read_subreg(lp, SR_TRX_STATUS, &status);
+	if (rc)
+		return rc;
+
+	dev_info(&lp->spi->dev, "Status: %02x\n", status);
+	if (status == STATE_P_ON) {
+		rc = at86rf230_write_subreg(lp, SR_TRX_CMD, STATE_TRX_OFF);
+		if (rc)
+			return rc;
+		msleep(1);
+		rc = at86rf230_read_subreg(lp, SR_TRX_STATUS, &status);
+		if (rc)
+			return rc;
+		dev_info(&lp->spi->dev, "Status: %02x\n", status);
+	}
+
+	rc = at86rf230_write_subreg(lp, SR_IRQ_MASK, 0xff); /* IRQ_TRX_UR |
+							     * IRQ_CCA_ED |
+							     * IRQ_TRX_END |
+							     * IRQ_PLL_UNL |
+							     * IRQ_PLL_LOCK
+							     */
+	if (rc)
+		return rc;
+
+	/* CLKM changes are applied immediately */
+	rc = at86rf230_write_subreg(lp, SR_CLKM_SHA_SEL, 0x00);
+	if (rc)
+		return rc;
+
+	/* Turn CLKM Off */
+	rc = at86rf230_write_subreg(lp, SR_CLKM_CTRL, 0x00);
+	if (rc)
+		return rc;
+	/* Wait the next SLEEP cycle */
+	msleep(100);
+
+	rc = at86rf230_write_subreg(lp, SR_TRX_CMD, STATE_TX_ON);
+	if (rc)
+		return rc;
+	msleep(1);
+
+	rc = at86rf230_read_subreg(lp, SR_TRX_STATUS, &status);
+	if (rc)
+		return rc;
+	dev_info(&lp->spi->dev, "Status: %02x\n", status);
+
+	rc = at86rf230_read_subreg(lp, SR_DVDD_OK, &status);
+	if (rc)
+		return rc;
+	if (!status) {
+		dev_err(&lp->spi->dev, "DVDD error\n");
+		return -EINVAL;
+	}
+
+	rc = at86rf230_read_subreg(lp, SR_AVDD_OK, &status);
+	if (rc)
+		return rc;
+	if (!status) {
+		dev_err(&lp->spi->dev, "AVDD error\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int at86rf230_suspend(struct spi_device *spi, pm_message_t message)
+{
+	return 0;
+}
+
+static int at86rf230_resume(struct spi_device *spi)
+{
+	return 0;
+}
+
+static int at86rf230_fill_data(struct spi_device *spi)
+{
+	struct at86rf230_local *lp = spi_get_drvdata(spi);
+	struct at86rf230_platform_data *pdata = spi->dev.platform_data;
+
+	if (!pdata) {
+		dev_err(&spi->dev, "no platform_data\n");
+		return -EINVAL;
+	}
+
+	lp->rstn = pdata->rstn;
+	lp->slp_tr = pdata->slp_tr;
+	lp->dig2 = pdata->dig2;
+
+	return 0;
+}
+
+static int __devinit at86rf230_probe(struct spi_device *spi)
+{
+	struct ieee802154_dev *dev;
+	struct at86rf230_local *lp;
+	u8 man_id_0, man_id_1;
+	int rc;
+	const char *chip;
+	int supported = 0;
+
+	if (!spi->irq) {
+		dev_err(&spi->dev, "no IRQ specified\n");
+		return -EINVAL;
+	}
+
+	dev = ieee802154_alloc_device(sizeof(*lp), &at86rf230_ops);
+	if (!dev)
+		return -ENOMEM;
+
+	lp = dev->priv;
+	lp->dev = dev;
+
+	lp->spi = spi;
+
+	dev->priv = lp;
+	dev->parent = &spi->dev;
+	dev->extra_tx_headroom = 0;
+	/* We do support only 2.4 Ghz */
+	dev->phy->channels_supported[0] = 0x7FFF800;
+	dev->flags = IEEE802154_HW_OMIT_CKSUM;
+
+	mutex_init(&lp->bmux);
+	INIT_WORK(&lp->irqwork, at86rf230_irqwork);
+	spin_lock_init(&lp->lock);
+	init_completion(&lp->tx_complete);
+
+	spi_set_drvdata(spi, lp);
+
+	rc = at86rf230_fill_data(spi);
+	if (rc)
+		goto err_fill;
+
+	rc = gpio_request(lp->rstn, "rstn");
+	if (rc)
+		goto err_rstn;
+
+	if (gpio_is_valid(lp->slp_tr)) {
+		rc = gpio_request(lp->slp_tr, "slp_tr");
+		if (rc)
+			goto err_slp_tr;
+	}
+
+	rc = gpio_direction_output(lp->rstn, 1);
+	if (rc)
+		goto err_gpio_dir;
+
+	if (gpio_is_valid(lp->slp_tr)) {
+		rc = gpio_direction_output(lp->slp_tr, 0);
+		if (rc)
+			goto err_gpio_dir;
+	}
+
+	/* Reset */
+	msleep(1);
+	gpio_set_value(lp->rstn, 0);
+	msleep(1);
+	gpio_set_value(lp->rstn, 1);
+	msleep(1);
+
+	rc = at86rf230_read_subreg(lp, SR_MAN_ID_0, &man_id_0);
+	if (rc)
+		goto err_gpio_dir;
+	rc = at86rf230_read_subreg(lp, SR_MAN_ID_1, &man_id_1);
+	if (rc)
+		goto err_gpio_dir;
+
+	if (man_id_1 != 0x00 || man_id_0 != 0x1f) {
+		dev_err(&spi->dev, "Non-Atmel dev found (MAN_ID %02x %02x)\n",
+			man_id_1, man_id_0);
+		rc = -EINVAL;
+		goto err_gpio_dir;
+	}
+
+	rc = at86rf230_read_subreg(lp, SR_PART_NUM, &lp->part);
+	if (rc)
+		goto err_gpio_dir;
+
+	rc = at86rf230_read_subreg(lp, SR_VERSION_NUM, &lp->vers);
+	if (rc)
+		goto err_gpio_dir;
+
+	switch (lp->part) {
+	case 2:
+		chip = "at86rf230";
+		/* supported = 1;  FIXME: should be easy to support; */
+		break;
+	case 3:
+		chip = "at86rf231";
+		supported = 1;
+		break;
+	default:
+		chip = "UNKNOWN";
+		break;
+	}
+
+	dev_info(&spi->dev, "Detected %s chip version %d\n", chip, lp->vers);
+	if (!supported) {
+		rc = -ENOTSUPP;
+		goto err_gpio_dir;
+	}
+
+	rc = at86rf230_hw_init(lp);
+	if (rc)
+		goto err_gpio_dir;
+
+	rc = request_irq(spi->irq, at86rf230_isr, IRQF_SHARED,
+			 dev_name(&spi->dev), lp);
+	if (rc)
+		goto err_gpio_dir;
+
+	rc = ieee802154_register_device(lp->dev);
+	if (rc)
+		goto err_irq;
+
+	return rc;
+
+	ieee802154_unregister_device(lp->dev);
+err_irq:
+	free_irq(spi->irq, lp);
+	flush_work(&lp->irqwork);
+err_gpio_dir:
+	if (gpio_is_valid(lp->slp_tr))
+		gpio_free(lp->slp_tr);
+err_slp_tr:
+	gpio_free(lp->rstn);
+err_rstn:
+err_fill:
+	spi_set_drvdata(spi, NULL);
+	mutex_destroy(&lp->bmux);
+	ieee802154_free_device(lp->dev);
+	return rc;
+}
+
+static int __devexit at86rf230_remove(struct spi_device *spi)
+{
+	struct at86rf230_local *lp = spi_get_drvdata(spi);
+
+	ieee802154_unregister_device(lp->dev);
+
+	free_irq(spi->irq, lp);
+	flush_work(&lp->irqwork);
+
+	if (gpio_is_valid(lp->slp_tr))
+		gpio_free(lp->slp_tr);
+	gpio_free(lp->rstn);
+
+	spi_set_drvdata(spi, NULL);
+	mutex_destroy(&lp->bmux);
+	ieee802154_free_device(lp->dev);
+
+	dev_dbg(&spi->dev, "unregistered at86rf230\n");
+	return 0;
+}
+
+static struct spi_driver at86rf230_driver = {
+	.driver = {
+		.name	= "at86rf230",
+		.owner	= THIS_MODULE,
+	},
+	.probe      = at86rf230_probe,
+	.remove     = __devexit_p(at86rf230_remove),
+	.suspend    = at86rf230_suspend,
+	.resume     = at86rf230_resume,
+};
+
+static int __init at86rf230_init(void)
+{
+	return spi_register_driver(&at86rf230_driver);
+}
+module_init(at86rf230_init);
+
+static void __exit at86rf230_exit(void)
+{
+	spi_unregister_driver(&at86rf230_driver);
+}
+module_exit(at86rf230_exit);
+
+MODULE_DESCRIPTION("AT86RF230 Transceiver Driver");
+MODULE_LICENSE("GPL v2");

include/linux/spi/at86rf230.h

+/*
+ * AT86RF230/RF231 driver
+ *
+ * Copyright (C) 2009-2012 Siemens AG
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Written by:
+ * Dmitry Eremin-Solenikov <dmitry.baryshkov@siemens.com>
+ */
+#ifndef AT86RF230_H
+#define AT86RF230_H
+
+struct at86rf230_platform_data {
+	int rstn;
+	int slp_tr;
+	int dig2;
+};
+
+#endif