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 <alex.aring@xxxxxxxxx>
---
drivers/net/ieee802154/at86rf230.c | 211 ++++++++++++++++---------------------
1 file changed, 89 insertions(+), 122 deletions(-)
diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c
index b8b0628..23b142c 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;
@@ -1775,7 +1741,8 @@ 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)
--
2.5.2
--
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