linux-stable/drivers/net/ieee802154/at86rf230.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * AT86RF230/RF231 driver
 *
 * Copyright (C) 2009-2012 Siemens AG
 *
 * Written by:
 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
 * Alexander Aring <aar@pengutronix.de>
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio/consumer.h>
#include <linux/hrtimer.h>
#include <linux/jiffies.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/property.h>
#include <linux/spi/spi.h>
#include <linux/regmap.h>
#include <linux/skbuff.h>
#include <linux/ieee802154.h>

#include <net/mac802154.h>
#include <net/cfg802154.h>

#include "at86rf230.h"

struct at86rf230_local;
/* at86rf2xx chip depend data.
 * All timings are in us.
 */
struct at86rf2xx_chip_data {
	u16 t_sleep_cycle;
	u16 t_channel_switch;
	u16 t_reset_to_off;
	u16 t_off_to_aack;
	u16 t_off_to_tx_on;
	u16 t_off_to_sleep;
	u16 t_sleep_to_off;
	u16 t_frame;
	u16 t_p_ack;
	int rssi_base_val;

	int (*set_channel)(struct at86rf230_local *, u8, u8);
	int (*set_txpower)(struct at86rf230_local *, s32);
};

#define AT86RF2XX_MAX_BUF		(127 + 3)
/* tx retries to access the TX_ON state
 * if it's above then force change will be started.
 *
 * We assume the max_frame_retries (7) value of 802.15.4 here.
 */
#define AT86RF2XX_MAX_TX_RETRIES	7
/* We use the recommended 5 minutes timeout to recalibrate */
#define AT86RF2XX_CAL_LOOP_TIMEOUT	(5 * 60 * HZ)

struct at86rf230_state_change {
	struct at86rf230_local *lp;
	int irq;

	struct hrtimer timer;
	struct spi_message msg;
	struct spi_transfer trx;
	u8 buf[AT86RF2XX_MAX_BUF];

	void (*complete)(void *context);
	u8 from_state;
	u8 to_state;
	int trac;

	bool free;
};

struct at86rf230_local {
	struct spi_device *spi;

	struct ieee802154_hw *hw;
	struct at86rf2xx_chip_data *data;
	struct regmap *regmap;
	struct gpio_desc *slp_tr;
	bool sleep;

	struct completion state_complete;
	struct at86rf230_state_change state;

	unsigned long cal_timeout;
	bool is_tx;
	bool is_tx_from_off;
	bool was_tx;
	u8 tx_retry;
	struct sk_buff *tx_skb;
	struct at86rf230_state_change tx;
};

#define AT86RF2XX_NUMREGS 0x3F

static void
at86rf230_async_state_change(struct at86rf230_local *lp,
			     struct at86rf230_state_change *ctx,
			     const u8 state, void (*complete)(void *context));

static inline void
at86rf230_sleep(struct at86rf230_local *lp)
{
	if (lp->slp_tr) {
		gpiod_set_value(lp->slp_tr, 1);
		usleep_range(lp->data->t_off_to_sleep,
			     lp->data->t_off_to_sleep + 10);
		lp->sleep = true;
	}
}

static inline void
at86rf230_awake(struct at86rf230_local *lp)
{
	if (lp->slp_tr) {
		gpiod_set_value(lp->slp_tr, 0);
		usleep_range(lp->data->t_sleep_to_off,
			     lp->data->t_sleep_to_off + 100);
		lp->sleep = false;
	}
}

static inline int
__at86rf230_write(struct at86rf230_local *lp,
		  unsigned int addr, unsigned int data)
{
	bool sleep = lp->sleep;
	int ret;

	/* awake for register setting if sleep */
	if (sleep)
		at86rf230_awake(lp);

	ret = regmap_write(lp->regmap, addr, data);

	/* sleep again if was sleeping */
	if (sleep)
		at86rf230_sleep(lp);

	return ret;
}

static inline int
__at86rf230_read(struct at86rf230_local *lp,
		 unsigned int addr, unsigned int *data)
{
	bool sleep = lp->sleep;
	int ret;

	/* awake for register setting if sleep */
	if (sleep)
		at86rf230_awake(lp);

	ret = regmap_read(lp->regmap, addr, data);

	/* sleep again if was sleeping */
	if (sleep)
		at86rf230_sleep(lp);

	return ret;
}

static inline int
at86rf230_read_subreg(struct at86rf230_local *lp,
		      unsigned int addr, unsigned int mask,
		      unsigned int shift, unsigned int *data)
{
	int rc;

	rc = __at86rf230_read(lp, addr, data);
	if (!rc)
		*data = (*data & mask) >> shift;

	return rc;
}

static inline int
at86rf230_write_subreg(struct at86rf230_local *lp,
		       unsigned int addr, unsigned int mask,
		       unsigned int shift, unsigned int data)
{
	bool sleep = lp->sleep;
	int ret;

	/* awake for register setting if sleep */
	if (sleep)
		at86rf230_awake(lp);

	ret = regmap_update_bits(lp->regmap, addr, mask, data << shift);

	/* sleep again if was sleeping */
	if (sleep)
		at86rf230_sleep(lp);

	return ret;
}

static inline void
at86rf230_slp_tr_rising_edge(struct at86rf230_local *lp)
{
	gpiod_set_value(lp->slp_tr, 1);
	udelay(1);
	gpiod_set_value(lp->slp_tr, 0);
}

static bool
at86rf230_reg_writeable(struct device *dev, unsigned int reg)
{
	switch (reg) {
	case RG_TRX_STATE:
	case RG_TRX_CTRL_0:
	case RG_TRX_CTRL_1:
	case RG_PHY_TX_PWR:
	case RG_PHY_ED_LEVEL:
	case RG_PHY_CC_CCA:
	case RG_CCA_THRES:
	case RG_RX_CTRL:
	case RG_SFD_VALUE:
	case RG_TRX_CTRL_2:
	case RG_ANT_DIV:
	case RG_IRQ_MASK:
	case RG_VREG_CTRL:
	case RG_BATMON:
	case RG_XOSC_CTRL:
	case RG_RX_SYN:
	case RG_XAH_CTRL_1:
	case RG_FTN_CTRL:
	case RG_PLL_CF:
	case RG_PLL_DCU:
	case RG_SHORT_ADDR_0:
	case RG_SHORT_ADDR_1:
	case RG_PAN_ID_0:
	case RG_PAN_ID_1:
	case RG_IEEE_ADDR_0:
	case RG_IEEE_ADDR_1:
	case RG_IEEE_ADDR_2:
	case RG_IEEE_ADDR_3:
	case RG_IEEE_ADDR_4:
	case RG_IEEE_ADDR_5:
	case RG_IEEE_ADDR_6:
	case RG_IEEE_ADDR_7:
	case RG_XAH_CTRL_0:
	case RG_CSMA_SEED_0:
	case RG_CSMA_SEED_1:
	case RG_CSMA_BE:
		return true;
	default:
		return false;
	}
}

static bool
at86rf230_reg_readable(struct device *dev, unsigned int reg)
{
	bool rc;

	/* all writeable are also readable */
	rc = at86rf230_reg_writeable(dev, reg);
	if (rc)
		return rc;

	/* readonly regs */
	switch (reg) {
	case RG_TRX_STATUS:
	case RG_PHY_RSSI:
	case RG_IRQ_STATUS:
	case RG_PART_NUM:
	case RG_VERSION_NUM:
	case RG_MAN_ID_1:
	case RG_MAN_ID_0:
		return true;
	default:
		return false;
	}
}

static bool
at86rf230_reg_volatile(struct device *dev, unsigned int reg)
{
	/* can be changed during runtime */
	switch (reg) {
	case RG_TRX_STATUS:
	case RG_TRX_STATE:
	case RG_PHY_RSSI:
	case RG_PHY_ED_LEVEL:
	case RG_IRQ_STATUS:
	case RG_VREG_CTRL:
	case RG_PLL_CF:
	case RG_PLL_DCU:
		return true;
	default:
		return false;
	}
}

static bool
at86rf230_reg_precious(struct device *dev, unsigned int reg)
{
	/* don't clear irq line on read */
	switch (reg) {
	case RG_IRQ_STATUS:
		return true;
	default:
		return false;
	}
}

static const struct regmap_config at86rf230_regmap_spi_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.write_flag_mask = CMD_REG | CMD_WRITE,
	.read_flag_mask = CMD_REG,
	.cache_type = REGCACHE_MAPLE,
	.max_register = AT86RF2XX_NUMREGS,
	.writeable_reg = at86rf230_reg_writeable,
	.readable_reg = at86rf230_reg_readable,
	.volatile_reg = at86rf230_reg_volatile,
	.precious_reg = at86rf230_reg_precious,
};

static void
at86rf230_async_error_recover_complete(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	if (ctx->free)
		kfree(ctx);

	if (lp->was_tx) {
		lp->was_tx = 0;
		ieee802154_xmit_hw_error(lp->hw, lp->tx_skb);
	}
}

static void
at86rf230_async_error_recover(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	if (lp->is_tx) {
		lp->was_tx = 1;
		lp->is_tx = 0;
	}

	at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON,
				     at86rf230_async_error_recover_complete);
}

static inline void
at86rf230_async_error(struct at86rf230_local *lp,
		      struct at86rf230_state_change *ctx, int rc)
{
	dev_err(&lp->spi->dev, "spi_async error %d\n", rc);

	at86rf230_async_state_change(lp, ctx, STATE_FORCE_TRX_OFF,
				     at86rf230_async_error_recover);
}

/* Generic function to get some register value in async mode */
static void
at86rf230_async_read_reg(struct at86rf230_local *lp, u8 reg,
			 struct at86rf230_state_change *ctx,
			 void (*complete)(void *context))
{
	int rc;

	u8 *tx_buf = ctx->buf;

	tx_buf[0] = (reg & CMD_REG_MASK) | CMD_REG;
	ctx->msg.complete = complete;
	rc = spi_async(lp->spi, &ctx->msg);
	if (rc)
		at86rf230_async_error(lp, ctx, rc);
}

static void
at86rf230_async_write_reg(struct at86rf230_local *lp, u8 reg, u8 val,
			  struct at86rf230_state_change *ctx,
			  void (*complete)(void *context))
{
	int rc;

	ctx->buf[0] = (reg & CMD_REG_MASK) | CMD_REG | CMD_WRITE;
	ctx->buf[1] = val;
	ctx->msg.complete = complete;
	rc = spi_async(lp->spi, &ctx->msg);
	if (rc)
		at86rf230_async_error(lp, ctx, rc);
}

static void
at86rf230_async_state_assert(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	const u8 *buf = ctx->buf;
	const u8 trx_state = buf[1] & TRX_STATE_MASK;

	/* Assert state change */
	if (trx_state != ctx->to_state) {
		/* Special handling if transceiver state is in
		 * STATE_BUSY_RX_AACK and a SHR was detected.
		 */
		if  (trx_state == STATE_BUSY_RX_AACK) {
			/* Undocumented race condition. If we send a state
			 * change to STATE_RX_AACK_ON the transceiver could
			 * change his state automatically to STATE_BUSY_RX_AACK
			 * if a SHR was detected. This is not an error, but we
			 * can't assert this.
			 */
			if (ctx->to_state == STATE_RX_AACK_ON)
				goto done;

			/* If we change to STATE_TX_ON without forcing and
			 * transceiver state is STATE_BUSY_RX_AACK, we wait
			 * 'tFrame + tPAck' receiving time. In this time the
			 * PDU should be received. If the transceiver is still
			 * in STATE_BUSY_RX_AACK, we run a force state change
			 * to STATE_TX_ON. This is a timeout handling, if the
			 * transceiver stucks in STATE_BUSY_RX_AACK.
			 *
			 * Additional we do several retries to try to get into
			 * TX_ON state without forcing. If the retries are
			 * higher or equal than AT86RF2XX_MAX_TX_RETRIES we
			 * will do a force change.
			 */
			if (ctx->to_state == STATE_TX_ON ||
			    ctx->to_state == STATE_TRX_OFF) {
				u8 state = ctx->to_state;

				if (lp->tx_retry >= AT86RF2XX_MAX_TX_RETRIES)
					state = STATE_FORCE_TRX_OFF;
				lp->tx_retry++;

				at86rf230_async_state_change(lp, ctx, state,
							     ctx->complete);
				return;
			}
		}

		dev_warn(&lp->spi->dev, "unexcept state change from 0x%02x to 0x%02x. Actual state: 0x%02x\n",
			 ctx->from_state, ctx->to_state, trx_state);
	}

done:
	if (ctx->complete)
		ctx->complete(context);
}

static enum hrtimer_restart at86rf230_async_state_timer(struct hrtimer *timer)
{
	struct at86rf230_state_change *ctx =
		container_of(timer, struct at86rf230_state_change, timer);
	struct at86rf230_local *lp = ctx->lp;

	at86rf230_async_read_reg(lp, RG_TRX_STATUS, ctx,
				 at86rf230_async_state_assert);

	return HRTIMER_NORESTART;
}

/* Do state change timing delay. */
static void
at86rf230_async_state_delay(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	struct at86rf2xx_chip_data *c = lp->data;
	bool force = false;
	ktime_t tim;

	/* The force state changes are will show as normal states in the
	 * state status subregister. We change the to_state to the
	 * corresponding one and remember if it was a force change, this
	 * differs if we do a state change from STATE_BUSY_RX_AACK.
	 */
	switch (ctx->to_state) {
	case STATE_FORCE_TX_ON:
		ctx->to_state = STATE_TX_ON;
		force = true;
		break;
	case STATE_FORCE_TRX_OFF:
		ctx->to_state = STATE_TRX_OFF;
		force = true;
		break;
	default:
		break;
	}

	switch (ctx->from_state) {
	case STATE_TRX_OFF:
		switch (ctx->to_state) {
		case STATE_RX_AACK_ON:
			tim = c->t_off_to_aack * NSEC_PER_USEC;
			/* state change from TRX_OFF to RX_AACK_ON to do a
			 * calibration, we need to reset the timeout for the
			 * next one.
			 */
			lp->cal_timeout = jiffies + AT86RF2XX_CAL_LOOP_TIMEOUT;
			goto change;
		case STATE_TX_ARET_ON:
		case STATE_TX_ON:
			tim = c->t_off_to_tx_on * NSEC_PER_USEC;
			/* state change from TRX_OFF to TX_ON or ARET_ON to do
			 * a calibration, we need to reset the timeout for the
			 * next one.
			 */
			lp->cal_timeout = jiffies + AT86RF2XX_CAL_LOOP_TIMEOUT;
			goto change;
		default:
			break;
		}
		break;
	case STATE_BUSY_RX_AACK:
		switch (ctx->to_state) {
		case STATE_TRX_OFF:
		case STATE_TX_ON:
			/* Wait for worst case receiving time if we
			 * didn't make a force change from BUSY_RX_AACK
			 * to TX_ON or TRX_OFF.
			 */
			if (!force) {
				tim = (c->t_frame + c->t_p_ack) * NSEC_PER_USEC;
				goto change;
			}
			break;
		default:
			break;
		}
		break;
	/* Default value, means RESET state */
	case STATE_P_ON:
		switch (ctx->to_state) {
		case STATE_TRX_OFF:
			tim = c->t_reset_to_off * NSEC_PER_USEC;
			goto change;
		default:
			break;
		}
		break;
	default:
		break;
	}

	/* Default delay is 1us in the most cases */
	udelay(1);
	at86rf230_async_state_timer(&ctx->timer);
	return;

change:
	hrtimer_start(&ctx->timer, tim, HRTIMER_MODE_REL);
}

static void
at86rf230_async_state_change_start(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	u8 *buf = ctx->buf;
	const u8 trx_state = buf[1] & TRX_STATE_MASK;

	/* Check for "possible" STATE_TRANSITION_IN_PROGRESS */
	if (trx_state == STATE_TRANSITION_IN_PROGRESS) {
		udelay(1);
		at86rf230_async_read_reg(lp, RG_TRX_STATUS, ctx,
					 at86rf230_async_state_change_start);
		return;
	}

	/* Check if we already are in the state which we change in */
	if (trx_state == ctx->to_state) {
		if (ctx->complete)
			ctx->complete(context);
		return;
	}

	/* Set current state to the context of state change */
	ctx->from_state = trx_state;

	/* Going into the next step for a state change which do a timing
	 * relevant delay.
	 */
	at86rf230_async_write_reg(lp, RG_TRX_STATE, ctx->to_state, ctx,
				  at86rf230_async_state_delay);
}

static void
at86rf230_async_state_change(struct at86rf230_local *lp,
			     struct at86rf230_state_change *ctx,
			     const u8 state, void (*complete)(void *context))
{
	/* Initialization for the state change context */
	ctx->to_state = state;
	ctx->complete = complete;
	at86rf230_async_read_reg(lp, RG_TRX_STATUS, ctx,
				 at86rf230_async_state_change_start);
}

static void
at86rf230_sync_state_change_complete(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	complete(&lp->state_complete);
}

/* This function do a sync framework above the async state change.
 * Some callbacks of the IEEE 802.15.4 driver interface need to be
 * handled synchronously.
 */
static int
at86rf230_sync_state_change(struct at86rf230_local *lp, unsigned int state)
{
	unsigned long rc;

	at86rf230_async_state_change(lp, &lp->state, state,
				     at86rf230_sync_state_change_complete);

	rc = wait_for_completion_timeout(&lp->state_complete,
					 msecs_to_jiffies(100));
	if (!rc) {
		at86rf230_async_error(lp, &lp->state, -ETIMEDOUT);
		return -ETIMEDOUT;
	}

	return 0;
}

static void
at86rf230_tx_complete(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	if (ctx->trac == IEEE802154_SUCCESS)
		ieee802154_xmit_complete(lp->hw, lp->tx_skb, false);
	else
		ieee802154_xmit_error(lp->hw, lp->tx_skb, ctx->trac);

	kfree(ctx);
}

static void
at86rf230_tx_on(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON,
				     at86rf230_tx_complete);
}

static void
at86rf230_tx_trac_check(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	u8 trac = TRAC_MASK(ctx->buf[1]);

	switch (trac) {
	case TRAC_SUCCESS:
	case TRAC_SUCCESS_DATA_PENDING:
		ctx->trac = IEEE802154_SUCCESS;
		break;
	case TRAC_CHANNEL_ACCESS_FAILURE:
		ctx->trac = IEEE802154_CHANNEL_ACCESS_FAILURE;
		break;
	case TRAC_NO_ACK:
		ctx->trac = IEEE802154_NO_ACK;
		break;
	default:
		ctx->trac = IEEE802154_SYSTEM_ERROR;
	}

	at86rf230_async_state_change(lp, ctx, STATE_TX_ON, at86rf230_tx_on);
}

static void
at86rf230_rx_read_frame_complete(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	const u8 *buf = ctx->buf;
	struct sk_buff *skb;
	u8 len, lqi;

	len = buf[1];
	if (!ieee802154_is_valid_psdu_len(len)) {
		dev_vdbg(&lp->spi->dev, "corrupted frame received\n");
		len = IEEE802154_MTU;
	}
	lqi = buf[2 + len];

	skb = dev_alloc_skb(IEEE802154_MTU);
	if (!skb) {
		dev_vdbg(&lp->spi->dev, "failed to allocate sk_buff\n");
		kfree(ctx);
		return;
	}

	skb_put_data(skb, buf + 2, len);
	ieee802154_rx_irqsafe(lp->hw, skb, lqi);
	kfree(ctx);
}

static void
at86rf230_rx_trac_check(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	u8 *buf = ctx->buf;
	int rc;

	buf[0] = CMD_FB;
	ctx->trx.len = AT86RF2XX_MAX_BUF;
	ctx->msg.complete = at86rf230_rx_read_frame_complete;
	rc = spi_async(lp->spi, &ctx->msg);
	if (rc) {
		ctx->trx.len = 2;
		at86rf230_async_error(lp, ctx, rc);
	}
}

static void
at86rf230_irq_trx_end(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	if (lp->is_tx) {
		lp->is_tx = 0;
		at86rf230_async_read_reg(lp, RG_TRX_STATE, ctx,
					 at86rf230_tx_trac_check);
	} else {
		at86rf230_async_read_reg(lp, RG_TRX_STATE, ctx,
					 at86rf230_rx_trac_check);
	}
}

static void
at86rf230_irq_status(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	const u8 *buf = ctx->buf;
	u8 irq = buf[1];

	enable_irq(lp->spi->irq);

	if (irq & IRQ_TRX_END) {
		at86rf230_irq_trx_end(ctx);
	} else {
		dev_err(&lp->spi->dev, "not supported irq %02x received\n",
			irq);
		kfree(ctx);
	}
}

static void
at86rf230_setup_spi_messages(struct at86rf230_local *lp,
			     struct at86rf230_state_change *state)
{
	state->lp = lp;
	state->irq = lp->spi->irq;
	spi_message_init(&state->msg);
	state->msg.context = state;
	state->trx.len = 2;
	state->trx.tx_buf = state->buf;
	state->trx.rx_buf = state->buf;
	spi_message_add_tail(&state->trx, &state->msg);
	hrtimer_init(&state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	state->timer.function = at86rf230_async_state_timer;
}

static irqreturn_t at86rf230_isr(int irq, void *data)
{
	struct at86rf230_local *lp = data;
	struct at86rf230_state_change *ctx;
	int rc;

	disable_irq_nosync(irq);

	ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
	if (!ctx) {
		enable_irq(irq);
		return IRQ_NONE;
	}

	at86rf230_setup_spi_messages(lp, ctx);
	/* tell on error handling to free ctx */
	ctx->free = true;

	ctx->buf[0] = (RG_IRQ_STATUS & CMD_REG_MASK) | CMD_REG;
	ctx->msg.complete = at86rf230_irq_status;
	rc = spi_async(lp->spi, &ctx->msg);
	if (rc) {
		at86rf230_async_error(lp, ctx, rc);
		enable_irq(irq);
		return IRQ_NONE;
	}

	return IRQ_HANDLED;
}

static void
at86rf230_write_frame_complete(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	ctx->trx.len = 2;

	if (lp->slp_tr)
		at86rf230_slp_tr_rising_edge(lp);
	else
		at86rf230_async_write_reg(lp, RG_TRX_STATE, STATE_BUSY_TX, ctx,
					  NULL);
}

static void
at86rf230_write_frame(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;
	struct sk_buff *skb = lp->tx_skb;
	u8 *buf = ctx->buf;
	int rc;

	lp->is_tx = 1;

	buf[0] = CMD_FB | CMD_WRITE;
	buf[1] = skb->len + 2;
	memcpy(buf + 2, skb->data, skb->len);
	ctx->trx.len = skb->len + 2;
	ctx->msg.complete = at86rf230_write_frame_complete;
	rc = spi_async(lp->spi, &ctx->msg);
	if (rc) {
		ctx->trx.len = 2;
		at86rf230_async_error(lp, ctx, rc);
	}
}

static void
at86rf230_xmit_tx_on(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	at86rf230_async_state_change(lp, ctx, STATE_TX_ARET_ON,
				     at86rf230_write_frame);
}

static void
at86rf230_xmit_start(void *context)
{
	struct at86rf230_state_change *ctx = context;
	struct at86rf230_local *lp = ctx->lp;

	/* check if we change from off state */
	if (lp->is_tx_from_off)
		at86rf230_async_state_change(lp, ctx, STATE_TX_ARET_ON,
					     at86rf230_write_frame);
	else
		at86rf230_async_state_change(lp, ctx, STATE_TX_ON,
					     at86rf230_xmit_tx_on);
}

static int
at86rf230_xmit(struct ieee802154_hw *hw, struct sk_buff *skb)
{
	struct at86rf230_local *lp = hw->priv;
	struct at86rf230_state_change *ctx = &lp->tx;

	lp->tx_skb = skb;
	lp->tx_retry = 0;

	/* After 5 minutes in PLL and the same frequency we run again the
	 * calibration loops which is recommended by at86rf2xx datasheets.
	 *
	 * The calibration is initiate by a state change from TRX_OFF
	 * to TX_ON, the lp->cal_timeout should be reinit by state_delay
	 * function then to start in the next 5 minutes.
	 */
	if (time_is_before_jiffies(lp->cal_timeout)) {
		lp->is_tx_from_off = true;
		at86rf230_async_state_change(lp, ctx, STATE_TRX_OFF,
					     at86rf230_xmit_start);
	} else {
		lp->is_tx_from_off = false;
		at86rf230_xmit_start(ctx);
	}

	return 0;
}

static int
at86rf230_ed(struct ieee802154_hw *hw, u8 *level)
{
	WARN_ON(!level);
	*level = 0xbe;
	return 0;
}

static int
at86rf230_start(struct ieee802154_hw *hw)
{
	struct at86rf230_local *lp = hw->priv;

	at86rf230_awake(lp);
	enable_irq(lp->spi->irq);

	return at86rf230_sync_state_change(lp, STATE_RX_AACK_ON);
}

static void
at86rf230_stop(struct ieee802154_hw *hw)
{
	struct at86rf230_local *lp = hw->priv;
	u8 csma_seed[2];

	at86rf230_sync_state_change(lp, STATE_FORCE_TRX_OFF);

	disable_irq(lp->spi->irq);

	/* It's recommended to set random new csma_seeds before sleep state.
	 * Makes only sense in the stop callback, not doing this inside of
	 * at86rf230_sleep, this is also used when we don't transmit afterwards
	 * when calling start callback again.
	 */
	get_random_bytes(csma_seed, ARRAY_SIZE(csma_seed));
	at86rf230_write_subreg(lp, SR_CSMA_SEED_0, csma_seed[0]);
	at86rf230_write_subreg(lp, SR_CSMA_SEED_1, csma_seed[1]);

	at86rf230_sleep(lp);
}

static int
at86rf23x_set_channel(struct at86rf230_local *lp, u8 page, u8 channel)
{
	return at86rf230_write_subreg(lp, SR_CHANNEL, channel);
}

#define AT86RF2XX_MAX_ED_LEVELS 0xF
static const s32 at86rf233_ed_levels[AT86RF2XX_MAX_ED_LEVELS + 1] = {
	-9400, -9200, -9000, -8800, -8600, -8400, -8200, -8000, -7800, -7600,
	-7400, -7200, -7000, -6800, -6600, -6400,
};

static const s32 at86rf231_ed_levels[AT86RF2XX_MAX_ED_LEVELS + 1] = {
	-9100, -8900, -8700, -8500, -8300, -8100, -7900, -7700, -7500, -7300,
	-7100, -6900, -6700, -6500, -6300, -6100,
};

static const s32 at86rf212_ed_levels_100[AT86RF2XX_MAX_ED_LEVELS + 1] = {
	-10000, -9800, -9600, -9400, -9200, -9000, -8800, -8600, -8400, -8200,
	-8000, -7800, -7600, -7400, -7200, -7000,
};

static const s32 at86rf212_ed_levels_98[AT86RF2XX_MAX_ED_LEVELS + 1] = {
	-9800, -9600, -9400, -9200, -9000, -8800, -8600, -8400, -8200, -8000,
	-7800, -7600, -7400, -7200, -7000, -6800,
};

static inline int
at86rf212_update_cca_ed_level(struct at86rf230_local *lp, int rssi_base_val)
{
	unsigned int cca_ed_thres;
	int rc;

	rc = at86rf230_read_subreg(lp, SR_CCA_ED_THRES, &cca_ed_thres);
	if (rc < 0)
		return rc;

	switch (rssi_base_val) {
	case -98:
		lp->hw->phy->supported.cca_ed_levels = at86rf212_ed_levels_98;
		lp->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(at86rf212_ed_levels_98);
		lp->hw->phy->cca_ed_level = at86rf212_ed_levels_98[cca_ed_thres];
		break;
	case -100:
		lp->hw->phy->supported.cca_ed_levels = at86rf212_ed_levels_100;
		lp->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(at86rf212_ed_levels_100);
		lp->hw->phy->cca_ed_level = at86rf212_ed_levels_100[cca_ed_thres];
		break;
	default:
		WARN_ON(1);
	}

	return 0;
}

static int
at86rf212_set_channel(struct at86rf230_local *lp, u8 page, u8 channel)
{
	int rc;

	if (channel == 0)
		rc = at86rf230_write_subreg(lp, SR_SUB_MODE, 0);
	else
		rc = at86rf230_write_subreg(lp, SR_SUB_MODE, 1);
	if (rc < 0)
		return rc;

	if (page == 0) {
		rc = at86rf230_write_subreg(lp, SR_BPSK_QPSK, 0);
		lp->data->rssi_base_val = -100;
	} else {
		rc = at86rf230_write_subreg(lp, SR_BPSK_QPSK, 1);
		lp->data->rssi_base_val = -98;
	}
	if (rc < 0)
		return rc;

	rc = at86rf212_update_cca_ed_level(lp, lp->data->rssi_base_val);
	if (rc < 0)
		return rc;

	return at86rf230_write_subreg(lp, SR_CHANNEL, channel);
}

static int
at86rf230_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
{
	struct at86rf230_local *lp = hw->priv;
	int rc;

	rc = lp->data->set_channel(lp, page, channel);
	/* Wait for PLL */
	usleep_range(lp->data->t_channel_switch,
		     lp->data->t_channel_switch + 10);

	lp->cal_timeout = jiffies + AT86RF2XX_CAL_LOOP_TIMEOUT;
	return rc;
}

static int
at86rf230_set_hw_addr_filt(struct ieee802154_hw *hw,
			   struct ieee802154_hw_addr_filt *filt,
			   unsigned long changed)
{
	struct at86rf230_local *lp = hw->priv;

	if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
		u16 addr = le16_to_cpu(filt->short_addr);

		dev_vdbg(&lp->spi->dev, "%s called for saddr\n", __func__);
		__at86rf230_write(lp, RG_SHORT_ADDR_0, addr);
		__at86rf230_write(lp, RG_SHORT_ADDR_1, addr >> 8);
	}

	if (changed & IEEE802154_AFILT_PANID_CHANGED) {
		u16 pan = le16_to_cpu(filt->pan_id);

		dev_vdbg(&lp->spi->dev, "%s called for pan id\n", __func__);
		__at86rf230_write(lp, RG_PAN_ID_0, pan);
		__at86rf230_write(lp, RG_PAN_ID_1, pan >> 8);
	}

	if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
		u8 i, addr[8];

		memcpy(addr, &filt->ieee_addr, 8);
		dev_vdbg(&lp->spi->dev, "%s called for IEEE addr\n", __func__);
		for (i = 0; i < 8; i++)
			__at86rf230_write(lp, RG_IEEE_ADDR_0 + i, addr[i]);
	}

	if (changed & IEEE802154_AFILT_PANC_CHANGED) {
		dev_vdbg(&lp->spi->dev, "%s called for panc change\n", __func__);
		if (filt->pan_coord)
			at86rf230_write_subreg(lp, SR_AACK_I_AM_COORD, 1);
		else
			at86rf230_write_subreg(lp, SR_AACK_I_AM_COORD, 0);
	}

	return 0;
}

#define AT86RF23X_MAX_TX_POWERS 0xF
static const s32 at86rf233_powers[AT86RF23X_MAX_TX_POWERS + 1] = {
	400, 370, 340, 300, 250, 200, 100, 0, -100, -200, -300, -400, -600,
	-800, -1200, -1700,
};

static const s32 at86rf231_powers[AT86RF23X_MAX_TX_POWERS + 1] = {
	300, 280, 230, 180, 130, 70, 0, -100, -200, -300, -400, -500, -700,
	-900, -1200, -1700,
};

#define AT86RF212_MAX_TX_POWERS 0x1F
static const s32 at86rf212_powers[AT86RF212_MAX_TX_POWERS + 1] = {
	500, 400, 300, 200, 100, 0, -100, -200, -300, -400, -500, -600, -700,
	-800, -900, -1000, -1100, -1200, -1300, -1400, -1500, -1600, -1700,
	-1800, -1900, -2000, -2100, -2200, -2300, -2400, -2500, -2600,
};

static int
at86rf23x_set_txpower(struct at86rf230_local *lp, s32 mbm)
{
	u32 i;

	for (i = 0; i < lp->hw->phy->supported.tx_powers_size; i++) {
		if (lp->hw->phy->supported.tx_powers[i] == mbm)
			return at86rf230_write_subreg(lp, SR_TX_PWR_23X, i);
	}

	return -EINVAL;
}

static int
at86rf212_set_txpower(struct at86rf230_local *lp, s32 mbm)
{
	u32 i;

	for (i = 0; i < lp->hw->phy->supported.tx_powers_size; i++) {
		if (lp->hw->phy->supported.tx_powers[i] == mbm)
			return at86rf230_write_subreg(lp, SR_TX_PWR_212, i);
	}

	return -EINVAL;
}

static int
at86rf230_set_txpower(struct ieee802154_hw *hw, s32 mbm)
{
	struct at86rf230_local *lp = hw->priv;

	return lp->data->set_txpower(lp, mbm);
}

static int
at86rf230_set_lbt(struct ieee802154_hw *hw, bool on)
{
	struct at86rf230_local *lp = hw->priv;

	return at86rf230_write_subreg(lp, SR_CSMA_LBT_MODE, on);
}

static int
at86rf230_set_cca_mode(struct ieee802154_hw *hw,
		       const struct wpan_phy_cca *cca)
{
	struct at86rf230_local *lp = hw->priv;
	u8 val;

	/* mapping 802.15.4 to driver spec */
	switch (cca->mode) {
	case NL802154_CCA_ENERGY:
		val = 1;
		break;
	case NL802154_CCA_CARRIER:
		val = 2;
		break;
	case NL802154_CCA_ENERGY_CARRIER:
		switch (cca->opt) {
		case NL802154_CCA_OPT_ENERGY_CARRIER_AND:
			val = 3;
			break;
		case NL802154_CCA_OPT_ENERGY_CARRIER_OR:
			val = 0;
			break;
		default:
			return -EINVAL;
		}
		break;
	default:
		return -EINVAL;
	}

	return at86rf230_write_subreg(lp, SR_CCA_MODE, val);
}

static int
at86rf230_set_cca_ed_level(struct ieee802154_hw *hw, s32 mbm)
{
	struct at86rf230_local *lp = hw->priv;
	u32 i;

	for (i = 0; i < hw->phy->supported.cca_ed_levels_size; i++) {
		if (hw->phy->supported.cca_ed_levels[i] == mbm)
			return at86rf230_write_subreg(lp, SR_CCA_ED_THRES, i);
	}

	return -EINVAL;
}

static int
at86rf230_set_csma_params(struct ieee802154_hw *hw, u8 min_be, u8 max_be,
			  u8 retries)
{
	struct at86rf230_local *lp = hw->priv;
	int rc;

	rc = at86rf230_write_subreg(lp, SR_MIN_BE, min_be);
	if (rc)
		return rc;

	rc = at86rf230_write_subreg(lp, SR_MAX_BE, max_be);
	if (rc)
		return rc;

	return at86rf230_write_subreg(lp, SR_MAX_CSMA_RETRIES, retries);
}

static int
at86rf230_set_frame_retries(struct ieee802154_hw *hw, s8 retries)
{
	struct at86rf230_local *lp = hw->priv;

	return at86rf230_write_subreg(lp, SR_MAX_FRAME_RETRIES, retries);
}

static int
at86rf230_set_promiscuous_mode(struct ieee802154_hw *hw, const bool on)
{
	struct at86rf230_local *lp = hw->priv;
	int rc;

	if (on) {
		rc = at86rf230_write_subreg(lp, SR_AACK_DIS_ACK, 1);
		if (rc < 0)
			return rc;

		rc = at86rf230_write_subreg(lp, SR_AACK_PROM_MODE, 1);
		if (rc < 0)
			return rc;
	} else {
		rc = at86rf230_write_subreg(lp, SR_AACK_PROM_MODE, 0);
		if (rc < 0)
			return rc;

		rc = at86rf230_write_subreg(lp, SR_AACK_DIS_ACK, 0);
		if (rc < 0)
			return rc;
	}

	return 0;
}

static const struct ieee802154_ops at86rf230_ops = {
	.owner = THIS_MODULE,
	.xmit_async = at86rf230_xmit,
	.ed = at86rf230_ed,
	.set_channel = at86rf230_channel,
	.start = at86rf230_start,
	.stop = at86rf230_stop,
	.set_hw_addr_filt = at86rf230_set_hw_addr_filt,
	.set_txpower = at86rf230_set_txpower,
	.set_lbt = at86rf230_set_lbt,
	.set_cca_mode = at86rf230_set_cca_mode,
	.set_cca_ed_level = at86rf230_set_cca_ed_level,
	.set_csma_params = at86rf230_set_csma_params,
	.set_frame_retries = at86rf230_set_frame_retries,
	.set_promiscuous_mode = at86rf230_set_promiscuous_mode,
};

static struct at86rf2xx_chip_data at86rf233_data = {
	.t_sleep_cycle = 330,
	.t_channel_switch = 11,
	.t_reset_to_off = 26,
	.t_off_to_aack = 80,
	.t_off_to_tx_on = 80,
	.t_off_to_sleep = 35,
	.t_sleep_to_off = 1000,
	.t_frame = 4096,
	.t_p_ack = 545,
	.rssi_base_val = -94,
	.set_channel = at86rf23x_set_channel,
	.set_txpower = at86rf23x_set_txpower,
};

static struct at86rf2xx_chip_data at86rf231_data = {
	.t_sleep_cycle = 330,
	.t_channel_switch = 24,
	.t_reset_to_off = 37,
	.t_off_to_aack = 110,
	.t_off_to_tx_on = 110,
	.t_off_to_sleep = 35,
	.t_sleep_to_off = 1000,
	.t_frame = 4096,
	.t_p_ack = 545,
	.rssi_base_val = -91,
	.set_channel = at86rf23x_set_channel,
	.set_txpower = at86rf23x_set_txpower,
};

static struct at86rf2xx_chip_data at86rf212_data = {
	.t_sleep_cycle = 330,
	.t_channel_switch = 11,
	.t_reset_to_off = 26,
	.t_off_to_aack = 200,
	.t_off_to_tx_on = 200,
	.t_off_to_sleep = 35,
	.t_sleep_to_off = 1000,
	.t_frame = 4096,
	.t_p_ack = 545,
	.rssi_base_val = -100,
	.set_channel = at86rf212_set_channel,
	.set_txpower = at86rf212_set_txpower,
};

static int at86rf230_hw_init(struct at86rf230_local *lp, u8 xtal_trim)
{
	int rc, irq_type, irq_pol = IRQ_ACTIVE_HIGH;
	unsigned int dvdd;
	u8 csma_seed[2];

	rc = at86rf230_sync_state_change(lp, STATE_FORCE_TRX_OFF);
	if (rc)
		return rc;

	irq_type = irq_get_trigger_type(lp->spi->irq);
	if (irq_type == IRQ_TYPE_EDGE_FALLING ||
	    irq_type == IRQ_TYPE_LEVEL_LOW)
		irq_pol = IRQ_ACTIVE_LOW;

	rc = at86rf230_write_subreg(lp, SR_IRQ_POLARITY, irq_pol);
	if (rc)
		return rc;

	rc = at86rf230_write_subreg(lp, SR_RX_SAFE_MODE, 1);
	if (rc)
		return rc;

	rc = at86rf230_write_subreg(lp, SR_IRQ_MASK, IRQ_TRX_END);
	if (rc)
		return rc;

	/* reset values differs in at86rf231 and at86rf233 */
	rc = at86rf230_write_subreg(lp, SR_IRQ_MASK_MODE, 0);
	if (rc)
		return rc;

	get_random_bytes(csma_seed, ARRAY_SIZE(csma_seed));
	rc = at86rf230_write_subreg(lp, SR_CSMA_SEED_0, csma_seed[0]);
	if (rc)
		return rc;
	rc = at86rf230_write_subreg(lp, SR_CSMA_SEED_1, csma_seed[1]);
	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 */
	usleep_range(lp->data->t_sleep_cycle,
		     lp->data->t_sleep_cycle + 100);

	/* xtal_trim value is calculated by:
	 * CL = 0.5 * (CX + CTRIM + CPAR)
	 *
	 * whereas:
	 * CL = capacitor of used crystal
	 * CX = connected capacitors at xtal pins
	 * CPAR = in all at86rf2xx datasheets this is a constant value 3 pF,
	 *	  but this is different on each board setup. You need to fine
	 *	  tuning this value via CTRIM.
	 * CTRIM = variable capacitor setting. Resolution is 0.3 pF range is
	 *	   0 pF upto 4.5 pF.
	 *
	 * Examples:
	 * atben transceiver:
	 *
	 * CL = 8 pF
	 * CX = 12 pF
	 * CPAR = 3 pF (We assume the magic constant from datasheet)
	 * CTRIM = 0.9 pF
	 *
	 * (12+0.9+3)/2 = 7.95 which is nearly at 8 pF
	 *
	 * xtal_trim = 0x3
	 *
	 * openlabs transceiver:
	 *
	 * CL = 16 pF
	 * CX = 22 pF
	 * CPAR = 3 pF (We assume the magic constant from datasheet)
	 * CTRIM = 4.5 pF
	 *
	 * (22+4.5+3)/2 = 14.75 which is the nearest value to 16 pF
	 *
	 * xtal_trim = 0xf
	 */
	rc = at86rf230_write_subreg(lp, SR_XTAL_TRIM, xtal_trim);
	if (rc)
		return rc;

	rc = at86rf230_read_subreg(lp, SR_DVDD_OK, &dvdd);
	if (rc)
		return rc;
	if (!dvdd) {
		dev_err(&lp->spi->dev, "DVDD error\n");
		return -EINVAL;
	}

	/* Force setting slotted operation bit to 0. Sometimes the atben
	 * sets this bit and I don't know why. We set this always force
	 * to zero while probing.
	 */
	return at86rf230_write_subreg(lp, SR_SLOTTED_OPERATION, 0);
}

static int
at86rf230_detect_device(struct at86rf230_local *lp)
{
	unsigned int part, version, val;
	u16 man_id = 0;
	const char *chip;
	int rc;

	rc = __at86rf230_read(lp, RG_MAN_ID_0, &val);
	if (rc)
		return rc;
	man_id |= val;

	rc = __at86rf230_read(lp, RG_MAN_ID_1, &val);
	if (rc)
		return rc;
	man_id |= (val << 8);

	rc = __at86rf230_read(lp, RG_PART_NUM, &part);
	if (rc)
		return rc;

	rc = __at86rf230_read(lp, RG_VERSION_NUM, &version);
	if (rc)
		return rc;

	if (man_id != 0x001f) {
		dev_err(&lp->spi->dev, "Non-Atmel dev found (MAN_ID %02x %02x)\n",
			man_id >> 8, man_id & 0xFF);
		return -EINVAL;
	}

	lp->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM |
			IEEE802154_HW_CSMA_PARAMS |
			IEEE802154_HW_FRAME_RETRIES | IEEE802154_HW_AFILT |
			IEEE802154_HW_PROMISCUOUS;

	lp->hw->phy->flags = WPAN_PHY_FLAG_TXPOWER |
			     WPAN_PHY_FLAG_CCA_ED_LEVEL |
			     WPAN_PHY_FLAG_CCA_MODE;

	lp->hw->phy->supported.cca_modes = BIT(NL802154_CCA_ENERGY) |
		BIT(NL802154_CCA_CARRIER) | BIT(NL802154_CCA_ENERGY_CARRIER);
	lp->hw->phy->supported.cca_opts = BIT(NL802154_CCA_OPT_ENERGY_CARRIER_AND) |
		BIT(NL802154_CCA_OPT_ENERGY_CARRIER_OR);

	lp->hw->phy->cca.mode = NL802154_CCA_ENERGY;

	switch (part) {
	case 2:
		chip = "at86rf230";
		rc = -ENOTSUPP;
		goto not_supp;
	case 3:
		chip = "at86rf231";
		lp->data = &at86rf231_data;
		lp->hw->phy->supported.channels[0] = 0x7FFF800;
		lp->hw->phy->current_channel = 11;
		lp->hw->phy->supported.tx_powers = at86rf231_powers;
		lp->hw->phy->supported.tx_powers_size = ARRAY_SIZE(at86rf231_powers);
		lp->hw->phy->supported.cca_ed_levels = at86rf231_ed_levels;
		lp->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(at86rf231_ed_levels);
		break;
	case 7:
		chip = "at86rf212";
		lp->data = &at86rf212_data;
		lp->hw->flags |= IEEE802154_HW_LBT;
		lp->hw->phy->supported.channels[0] = 0x00007FF;
		lp->hw->phy->supported.channels[2] = 0x00007FF;
		lp->hw->phy->current_channel = 5;
		lp->hw->phy->supported.lbt = NL802154_SUPPORTED_BOOL_BOTH;
		lp->hw->phy->supported.tx_powers = at86rf212_powers;
		lp->hw->phy->supported.tx_powers_size = ARRAY_SIZE(at86rf212_powers);
		lp->hw->phy->supported.cca_ed_levels = at86rf212_ed_levels_100;
		lp->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(at86rf212_ed_levels_100);
		break;
	case 11:
		chip = "at86rf233";
		lp->data = &at86rf233_data;
		lp->hw->phy->supported.channels[0] = 0x7FFF800;
		lp->hw->phy->current_channel = 13;
		lp->hw->phy->supported.tx_powers = at86rf233_powers;
		lp->hw->phy->supported.tx_powers_size = ARRAY_SIZE(at86rf233_powers);
		lp->hw->phy->supported.cca_ed_levels = at86rf233_ed_levels;
		lp->hw->phy->supported.cca_ed_levels_size = ARRAY_SIZE(at86rf233_ed_levels);
		break;
	default:
		chip = "unknown";
		rc = -ENOTSUPP;
		goto not_supp;
	}

	lp->hw->phy->cca_ed_level = lp->hw->phy->supported.cca_ed_levels[7];
	lp->hw->phy->transmit_power = lp->hw->phy->supported.tx_powers[0];

not_supp:
	dev_info(&lp->spi->dev, "Detected %s chip version %d\n", chip, version);

	return rc;
}

static int at86rf230_probe(struct spi_device *spi)
{
	struct ieee802154_hw *hw;
	struct at86rf230_local *lp;
	struct gpio_desc *slp_tr;
	struct gpio_desc *rstn;
	unsigned int status;
	int rc, irq_type;
	u8 xtal_trim;

	if (!spi->irq) {
		dev_err(&spi->dev, "no IRQ specified\n");
		return -EINVAL;
	}

	rc = device_property_read_u8(&spi->dev, "xtal-trim", &xtal_trim);
	if (rc < 0) {
		if (rc != -EINVAL) {
			dev_err(&spi->dev,
				"failed to parse xtal-trim: %d\n", rc);
			return rc;
		}
		xtal_trim = 0;
	}

	rstn = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_LOW);
	rc = PTR_ERR_OR_ZERO(rstn);
	if (rc)
		return rc;

	gpiod_set_consumer_name(rstn, "rstn");

	slp_tr = devm_gpiod_get_optional(&spi->dev, "sleep", GPIOD_OUT_LOW);
	rc = PTR_ERR_OR_ZERO(slp_tr);
	if (rc)
		return rc;

	gpiod_set_consumer_name(slp_tr, "slp_tr");

	/* Reset */
	if (rstn) {
		udelay(1);
		gpiod_set_value_cansleep(rstn, 1);
		udelay(1);
		gpiod_set_value_cansleep(rstn, 0);
		usleep_range(120, 240);
	}

	hw = ieee802154_alloc_hw(sizeof(*lp), &at86rf230_ops);
	if (!hw)
		return -ENOMEM;

	lp = hw->priv;
	lp->hw = hw;
	lp->spi = spi;
	lp->slp_tr = slp_tr;
	hw->parent = &spi->dev;
	ieee802154_random_extended_addr(&hw->phy->perm_extended_addr);

	lp->regmap = devm_regmap_init_spi(spi, &at86rf230_regmap_spi_config);
	if (IS_ERR(lp->regmap)) {
		rc = PTR_ERR(lp->regmap);
		dev_err(&spi->dev, "Failed to allocate register map: %d\n",
			rc);
		goto free_dev;
	}

	at86rf230_setup_spi_messages(lp, &lp->state);
	at86rf230_setup_spi_messages(lp, &lp->tx);

	rc = at86rf230_detect_device(lp);
	if (rc < 0)
		goto free_dev;

	init_completion(&lp->state_complete);

	spi_set_drvdata(spi, lp);

	rc = at86rf230_hw_init(lp, xtal_trim);
	if (rc)
		goto free_dev;

	/* Read irq status register to reset irq line */
	rc = at86rf230_read_subreg(lp, RG_IRQ_STATUS, 0xff, 0, &status);
	if (rc)
		goto free_dev;

	irq_type = irq_get_trigger_type(spi->irq);
	if (!irq_type)
		irq_type = IRQF_TRIGGER_HIGH;

	rc = devm_request_irq(&spi->dev, spi->irq, at86rf230_isr,
			      IRQF_SHARED | irq_type, dev_name(&spi->dev), lp);
	if (rc)
		goto free_dev;

	/* disable_irq by default and wait for starting hardware */
	disable_irq(spi->irq);

	/* going into sleep by default */
	at86rf230_sleep(lp);

	rc = ieee802154_register_hw(lp->hw);
	if (rc)
		goto free_dev;

	return rc;

free_dev:
	ieee802154_free_hw(lp->hw);

	return rc;
}

static void at86rf230_remove(struct spi_device *spi)
{
	struct at86rf230_local *lp = spi_get_drvdata(spi);

	/* mask all at86rf230 irq's */
	at86rf230_write_subreg(lp, SR_IRQ_MASK, 0);
	ieee802154_unregister_hw(lp->hw);
	ieee802154_free_hw(lp->hw);
	dev_dbg(&spi->dev, "unregistered at86rf230\n");
}

static const struct of_device_id at86rf230_of_match[] = {
	{ .compatible = "atmel,at86rf230", },
	{ .compatible = "atmel,at86rf231", },
	{ .compatible = "atmel,at86rf233", },
	{ .compatible = "atmel,at86rf212", },
	{ },
};
MODULE_DEVICE_TABLE(of, at86rf230_of_match);

static const struct spi_device_id at86rf230_device_id[] = {
	{ .name = "at86rf230", },
	{ .name = "at86rf231", },
	{ .name = "at86rf233", },
	{ .name = "at86rf212", },
	{ },
};
MODULE_DEVICE_TABLE(spi, at86rf230_device_id);

static struct spi_driver at86rf230_driver = {
	.id_table = at86rf230_device_id,
	.driver = {
		.of_match_table = at86rf230_of_match,
		.name	= "at86rf230",
	},
	.probe      = at86rf230_probe,
	.remove     = at86rf230_remove,
};

module_spi_driver(at86rf230_driver);

MODULE_DESCRIPTION("AT86RF230 Transceiver Driver");
MODULE_LICENSE("GPL v2");