From 57c1bc7ea8a4857070722c23ce98e01f256c9306 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Mon, 21 Sep 2015 09:37:54 +0200 Subject: [PATCH] at86rf230: support edge triggered irq This patch adds support for edge triggered irq types. We remove the locking for irq resources by enable/disable irq and allocate directly some heap buffer at isr. We have still a enable/disable irq path but this is for level-triggered irq's which need to be disabled until spi_async clear the irq line. There is usually a little race condition between "irq line cleared" and "enable_irq". When in this time a edge triggered irq arrived, we will not recognize this interrupt. This case can't happend at at86rf230. The reason is that we unmask TRX_END irq's only which indicates a transmit or receive completion, which depends on the current state. On Transmit: TRX_END arrived and transceiver is in TX_ARET_ON state again, in this state no other TRX_END can happen until we leave the state. On Receive: This is protected with the RX_SAFE_MODE bit which leaves the transceiver in RX_AACK_BUSY until we readed the framebuffer. In this state no other TRX_END can happen. Tested with RPi where I first detected issues between edge/level irq's. Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- drivers/net/ieee802154/at86rf230.c | 213 ++++++++++++----------------- 1 file changed, 90 insertions(+), 123 deletions(-) diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c index 9756e6451038..de6e4fa2d6aa 100644 --- a/drivers/net/ieee802154/at86rf230.c +++ b/drivers/net/ieee802154/at86rf230.c @@ -81,7 +81,7 @@ struct at86rf230_state_change { u8 from_state; u8 to_state; - bool irq_enable; + bool free; }; struct at86rf230_trac { @@ -105,8 +105,6 @@ struct at86rf230_local { struct completion state_complete; struct at86rf230_state_change state; - struct at86rf230_state_change irq; - unsigned long cal_timeout; bool is_tx; bool is_tx_from_off; @@ -122,8 +120,7 @@ struct at86rf230_local { static void at86rf230_async_state_change(struct at86rf230_local *lp, struct at86rf230_state_change *ctx, - const u8 state, void (*complete)(void *context), - const bool irq_enable); + const u8 state, void (*complete)(void *context)); static inline void at86rf230_sleep(struct at86rf230_local *lp) @@ -352,8 +349,10 @@ at86rf230_async_error_recover(void *context) struct at86rf230_local *lp = ctx->lp; lp->is_tx = 0; - at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON, NULL, false); + at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON, NULL); ieee802154_wake_queue(lp->hw); + if (ctx->free) + kfree(ctx); } static inline void @@ -363,15 +362,14 @@ at86rf230_async_error(struct at86rf230_local *lp, 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, false); + at86rf230_async_error_recover); } /* Generic function to get some register value in async mode */ static void -at86rf230_async_read_reg(struct at86rf230_local *lp, const u8 reg, +at86rf230_async_read_reg(struct at86rf230_local *lp, u8 reg, struct at86rf230_state_change *ctx, - void (*complete)(void *context), - const bool irq_enable) + void (*complete)(void *context)) { int rc; @@ -379,14 +377,24 @@ at86rf230_async_read_reg(struct at86rf230_local *lp, const u8 reg, tx_buf[0] = (reg & CMD_REG_MASK) | CMD_REG; ctx->msg.complete = complete; - ctx->irq_enable = irq_enable; rc = spi_async(lp->spi, &ctx->msg); - if (rc) { - if (irq_enable) - enable_irq(ctx->irq); - + 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 @@ -434,8 +442,7 @@ at86rf230_async_state_assert(void *context) lp->tx_retry++; at86rf230_async_state_change(lp, ctx, state, - ctx->complete, - ctx->irq_enable); + ctx->complete); return; } } @@ -456,8 +463,7 @@ static enum hrtimer_restart at86rf230_async_state_timer(struct hrtimer *timer) struct at86rf230_local *lp = ctx->lp; at86rf230_async_read_reg(lp, RG_TRX_STATUS, ctx, - at86rf230_async_state_assert, - ctx->irq_enable); + at86rf230_async_state_assert); return HRTIMER_NORESTART; } @@ -562,14 +568,12 @@ at86rf230_async_state_change_start(void *context) struct at86rf230_local *lp = ctx->lp; u8 *buf = ctx->buf; const u8 trx_state = buf[1] & TRX_STATE_MASK; - int rc; /* 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, - ctx->irq_enable); + at86rf230_async_state_change_start); return; } @@ -586,31 +590,20 @@ at86rf230_async_state_change_start(void *context) /* Going into the next step for a state change which do a timing * relevant delay. */ - buf[0] = (RG_TRX_STATE & CMD_REG_MASK) | CMD_REG | CMD_WRITE; - buf[1] = ctx->to_state; - ctx->msg.complete = at86rf230_async_state_delay; - rc = spi_async(lp->spi, &ctx->msg); - if (rc) { - if (ctx->irq_enable) - enable_irq(ctx->irq); - - at86rf230_async_error(lp, ctx, rc); - } + 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), - const bool irq_enable) + const u8 state, void (*complete)(void *context)) { /* Initialization for the state change context */ ctx->to_state = state; ctx->complete = complete; - ctx->irq_enable = irq_enable; at86rf230_async_read_reg(lp, RG_TRX_STATUS, ctx, - at86rf230_async_state_change_start, - irq_enable); + at86rf230_async_state_change_start); } static void @@ -632,8 +625,7 @@ 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, - false); + at86rf230_sync_state_change_complete); rc = wait_for_completion_timeout(&lp->state_complete, msecs_to_jiffies(100)); @@ -651,9 +643,8 @@ at86rf230_tx_complete(void *context) struct at86rf230_state_change *ctx = context; struct at86rf230_local *lp = ctx->lp; - enable_irq(ctx->irq); - ieee802154_xmit_complete(lp->hw, lp->tx_skb, false); + kfree(ctx); } static void @@ -663,7 +654,7 @@ at86rf230_tx_on(void *context) struct at86rf230_local *lp = ctx->lp; at86rf230_async_state_change(lp, ctx, STATE_RX_AACK_ON, - at86rf230_tx_complete, true); + at86rf230_tx_complete); } static void @@ -697,8 +688,7 @@ at86rf230_tx_trac_check(void *context) } } - at86rf230_async_state_change(lp, &lp->irq, STATE_TX_ON, - at86rf230_tx_on, true); + at86rf230_async_state_change(lp, ctx, STATE_TX_ON, at86rf230_tx_on); } static void @@ -706,7 +696,6 @@ at86rf230_rx_read_frame_complete(void *context) { struct at86rf230_state_change *ctx = context; struct at86rf230_local *lp = ctx->lp; - u8 rx_local_buf[AT86RF2XX_MAX_BUF]; const u8 *buf = ctx->buf; struct sk_buff *skb; u8 len, lqi; @@ -718,18 +707,16 @@ at86rf230_rx_read_frame_complete(void *context) } lqi = buf[2 + len]; - memcpy(rx_local_buf, buf + 2, len); - ctx->trx.len = 2; - enable_irq(ctx->irq); - skb = dev_alloc_skb(IEEE802154_MTU); if (!skb) { dev_vdbg(&lp->spi->dev, "failed to allocate sk_buff\n"); + kfree(ctx); return; } - memcpy(skb_put(skb, len), rx_local_buf, len); + memcpy(skb_put(skb, len), buf + 2, len); ieee802154_rx_irqsafe(lp->hw, skb, lqi); + kfree(ctx); } static void @@ -765,21 +752,23 @@ at86rf230_rx_trac_check(void *context) rc = spi_async(lp->spi, &ctx->msg); if (rc) { ctx->trx.len = 2; - enable_irq(ctx->irq); at86rf230_async_error(lp, ctx, rc); } } static void -at86rf230_irq_trx_end(struct at86rf230_local *lp) +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, &lp->irq, - at86rf230_tx_trac_check, true); + at86rf230_async_read_reg(lp, RG_TRX_STATE, ctx, + at86rf230_tx_trac_check); } else { - at86rf230_async_read_reg(lp, RG_TRX_STATE, &lp->irq, - at86rf230_rx_trac_check, true); + at86rf230_async_read_reg(lp, RG_TRX_STATE, ctx, + at86rf230_rx_trac_check); } } @@ -789,32 +778,59 @@ at86rf230_irq_status(void *context) struct at86rf230_state_change *ctx = context; struct at86rf230_local *lp = ctx->lp; const u8 *buf = ctx->buf; - const u8 irq = buf[1]; + u8 irq = buf[1]; + + enable_irq(lp->spi->irq); if (irq & IRQ_TRX_END) { - at86rf230_irq_trx_end(lp); + at86rf230_irq_trx_end(ctx); } else { - enable_irq(ctx->irq); 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 = &lp->irq; - u8 *buf = ctx->buf; + struct at86rf230_state_change *ctx; int rc; disable_irq_nosync(irq); - buf[0] = (RG_IRQ_STATUS & CMD_REG_MASK) | CMD_REG; + 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) { - enable_irq(irq); at86rf230_async_error(lp, ctx, rc); + enable_irq(irq); return IRQ_NONE; } @@ -826,21 +842,14 @@ at86rf230_write_frame_complete(void *context) { struct at86rf230_state_change *ctx = context; struct at86rf230_local *lp = ctx->lp; - u8 *buf = ctx->buf; - int rc; ctx->trx.len = 2; - if (gpio_is_valid(lp->slp_tr)) { + if (gpio_is_valid(lp->slp_tr)) at86rf230_slp_tr_rising_edge(lp); - } else { - buf[0] = (RG_TRX_STATE & CMD_REG_MASK) | CMD_REG | CMD_WRITE; - buf[1] = STATE_BUSY_TX; - ctx->msg.complete = NULL; - rc = spi_async(lp->spi, &ctx->msg); - if (rc) - at86rf230_async_error(lp, ctx, rc); - } + else + at86rf230_async_write_reg(lp, RG_TRX_STATE, STATE_BUSY_TX, ctx, + NULL); } static void @@ -873,7 +882,7 @@ at86rf230_xmit_tx_on(void *context) struct at86rf230_local *lp = ctx->lp; at86rf230_async_state_change(lp, ctx, STATE_TX_ARET_ON, - at86rf230_write_frame, false); + at86rf230_write_frame); } static void @@ -886,12 +895,10 @@ at86rf230_xmit_start(void *context) if (lp->is_tx_from_off) { lp->is_tx_from_off = false; at86rf230_async_state_change(lp, ctx, STATE_TX_ARET_ON, - at86rf230_write_frame, - false); + at86rf230_write_frame); } else { at86rf230_async_state_change(lp, ctx, STATE_TX_ON, - at86rf230_xmit_tx_on, - false); + at86rf230_xmit_tx_on); } } @@ -914,7 +921,7 @@ at86rf230_xmit(struct ieee802154_hw *hw, struct sk_buff *skb) 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, false); + at86rf230_xmit_start); } else { at86rf230_xmit_start(ctx); } @@ -1373,10 +1380,6 @@ static int at86rf230_hw_init(struct at86rf230_local *lp, u8 xtal_trim) return rc; irq_type = irq_get_trigger_type(lp->spi->irq); - if (irq_type == IRQ_TYPE_EDGE_RISING || - irq_type == IRQ_TYPE_EDGE_FALLING) - dev_warn(&lp->spi->dev, - "Using edge triggered irq's are not recommended, because it can cause races and result in a non-functional driver!\n"); if (irq_type == IRQ_TYPE_EDGE_FALLING || irq_type == IRQ_TYPE_LEVEL_LOW) irq_pol = IRQ_ACTIVE_LOW; @@ -1602,43 +1605,6 @@ not_supp: return rc; } -static void -at86rf230_setup_spi_messages(struct at86rf230_local *lp) -{ - lp->state.lp = lp; - lp->state.irq = lp->spi->irq; - spi_message_init(&lp->state.msg); - lp->state.msg.context = &lp->state; - lp->state.trx.len = 2; - lp->state.trx.tx_buf = lp->state.buf; - lp->state.trx.rx_buf = lp->state.buf; - spi_message_add_tail(&lp->state.trx, &lp->state.msg); - hrtimer_init(&lp->state.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - lp->state.timer.function = at86rf230_async_state_timer; - - lp->irq.lp = lp; - lp->irq.irq = lp->spi->irq; - spi_message_init(&lp->irq.msg); - lp->irq.msg.context = &lp->irq; - lp->irq.trx.len = 2; - lp->irq.trx.tx_buf = lp->irq.buf; - lp->irq.trx.rx_buf = lp->irq.buf; - spi_message_add_tail(&lp->irq.trx, &lp->irq.msg); - hrtimer_init(&lp->irq.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - lp->irq.timer.function = at86rf230_async_state_timer; - - lp->tx.lp = lp; - lp->tx.irq = lp->spi->irq; - spi_message_init(&lp->tx.msg); - lp->tx.msg.context = &lp->tx; - lp->tx.trx.len = 2; - lp->tx.trx.tx_buf = lp->tx.buf; - lp->tx.trx.rx_buf = lp->tx.buf; - spi_message_add_tail(&lp->tx.trx, &lp->tx.msg); - hrtimer_init(&lp->tx.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - lp->tx.timer.function = at86rf230_async_state_timer; -} - #ifdef CONFIG_IEEE802154_AT86RF230_DEBUGFS static struct dentry *at86rf230_debugfs_root; @@ -1760,7 +1726,8 @@ static int at86rf230_probe(struct spi_device *spi) goto free_dev; } - at86rf230_setup_spi_messages(lp); + at86rf230_setup_spi_messages(lp, &lp->state); + at86rf230_setup_spi_messages(lp, &lp->tx); rc = at86rf230_detect_device(lp); if (rc < 0)