--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Interrupt bottom half (BH).
+ *
+ * Copyright (c) 2017-2019, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#include <linux/gpio/consumer.h>
+#include <net/mac80211.h>
+
+#include "bh.h"
+#include "wfx.h"
+#include "hwio.h"
+#include "hif_api_cmd.h"
+
+static void device_wakeup(struct wfx_dev *wdev)
+{
+ if (!wdev->pdata.gpio_wakeup)
+ return;
+ if (gpiod_get_value(wdev->pdata.gpio_wakeup))
+ return;
+
+ gpiod_set_value(wdev->pdata.gpio_wakeup, 1);
+ if (wfx_api_older_than(wdev, 1, 4)) {
+ if (!completion_done(&wdev->hif.ctrl_ready))
+ udelay(2000);
+ } else {
+ // completion.h does not provide any function to wait
+ // completion without consume it (a kind of
+ // wait_for_completion_done_timeout()). So we have to emulate
+ // it.
+ if (wait_for_completion_timeout(&wdev->hif.ctrl_ready, msecs_to_jiffies(2) + 1))
+ complete(&wdev->hif.ctrl_ready);
+ else
+ dev_err(wdev->dev, "timeout while wake up chip\n");
+ }
+}
+
+static void device_release(struct wfx_dev *wdev)
+{
+ if (!wdev->pdata.gpio_wakeup)
+ return;
+
+ gpiod_set_value(wdev->pdata.gpio_wakeup, 0);
+}
+
+static int rx_helper(struct wfx_dev *wdev, size_t read_len, int *is_cnf)
+{
+ struct sk_buff *skb;
+ struct hif_msg *hif;
+ size_t alloc_len;
+ size_t computed_len;
+ int release_count;
+ int piggyback = 0;
+
+ WARN_ON(read_len < 4);
+ WARN(read_len > round_down(0xFFF, 2) * sizeof(u16),
+ "%s: request exceed WFx capability", __func__);
+
+ // Add 2 to take into account piggyback size
+ alloc_len = wdev->hwbus_ops->align_size(wdev->hwbus_priv, read_len + 2);
+ skb = dev_alloc_skb(alloc_len);
+ if (!skb)
+ return -ENOMEM;
+
+ if (wfx_data_read(wdev, skb->data, alloc_len))
+ goto err;
+
+ piggyback = le16_to_cpup((u16 *) (skb->data + alloc_len - 2));
+
+ hif = (struct hif_msg *) skb->data;
+ WARN(hif->encrypted & 0x1, "unsupported encryption type");
+ if (hif->encrypted == 0x2) {
+ BUG(); // Not yet implemented
+ } else {
+ le16_to_cpus(hif->len);
+ computed_len = round_up(hif->len, 2);
+ }
+ if (computed_len != read_len) {
+ dev_err(wdev->dev, "inconsistent message length: %zu != %zu\n",
+ computed_len, read_len);
+ print_hex_dump(KERN_INFO, "hif: ", DUMP_PREFIX_OFFSET, 16, 1,
+ hif, read_len, true);
+ goto err;
+ }
+
+ if (!(hif->id & HIF_ID_IS_INDICATION)) {
+ (*is_cnf)++;
+ if (hif->id == HIF_CNF_ID_MULTI_TRANSMIT)
+ release_count = le32_to_cpu(((struct hif_cnf_multi_transmit *) hif->body)->num_tx_confs);
+ else
+ release_count = 1;
+ WARN(wdev->hif.tx_buffers_used < release_count, "corrupted buffer counter");
+ wdev->hif.tx_buffers_used -= release_count;
+ if (!wdev->hif.tx_buffers_used)
+ wake_up(&wdev->hif.tx_buffers_empty);
+ }
+
+ if (hif->id != HIF_IND_ID_EXCEPTION && hif->id != HIF_IND_ID_ERROR) {
+ if (hif->seqnum != wdev->hif.rx_seqnum)
+ dev_warn(wdev->dev, "wrong message sequence: %d != %d\n",
+ hif->seqnum, wdev->hif.rx_seqnum);
+ wdev->hif.rx_seqnum = (hif->seqnum + 1) % (HIF_COUNTER_MAX + 1);
+ }
+
+ skb_put(skb, hif->len);
+ dev_kfree_skb(skb); /* FIXME: handle received data */
+
+ return piggyback;
+
+err:
+ if (skb)
+ dev_kfree_skb(skb);
+ return -EIO;
+}
+
+static int bh_work_rx(struct wfx_dev *wdev, int max_msg, int *num_cnf)
+{
+ size_t len;
+ int i;
+ int ctrl_reg, piggyback;
+
+ piggyback = 0;
+ for (i = 0; i < max_msg; i++) {
+ if (piggyback & CTRL_NEXT_LEN_MASK)
+ ctrl_reg = piggyback;
+ else if (try_wait_for_completion(&wdev->hif.ctrl_ready))
+ ctrl_reg = atomic_xchg(&wdev->hif.ctrl_reg, 0);
+ else
+ ctrl_reg = 0;
+ if (!(ctrl_reg & CTRL_NEXT_LEN_MASK))
+ return i;
+ // ctrl_reg units are 16bits words
+ len = (ctrl_reg & CTRL_NEXT_LEN_MASK) * 2;
+ piggyback = rx_helper(wdev, len, num_cnf);
+ if (piggyback < 0)
+ return i;
+ if (!(piggyback & CTRL_WLAN_READY))
+ dev_err(wdev->dev, "unexpected piggyback value: ready bit not set: %04x\n",
+ piggyback);
+ }
+ if (piggyback & CTRL_NEXT_LEN_MASK) {
+ ctrl_reg = atomic_xchg(&wdev->hif.ctrl_reg, piggyback);
+ complete(&wdev->hif.ctrl_ready);
+ if (ctrl_reg)
+ dev_err(wdev->dev, "unexpected IRQ happened: %04x/%04x\n",
+ ctrl_reg, piggyback);
+ }
+ return i;
+}
+
+static void tx_helper(struct wfx_dev *wdev, struct hif_msg *hif)
+{
+ int ret;
+ void *data;
+ bool is_encrypted = false;
+ size_t len = le16_to_cpu(hif->len);
+
+ BUG_ON(len < sizeof(*hif));
+
+ hif->seqnum = wdev->hif.tx_seqnum;
+ wdev->hif.tx_seqnum = (wdev->hif.tx_seqnum + 1) % (HIF_COUNTER_MAX + 1);
+
+ data = hif;
+ WARN(len > wdev->hw_caps.size_inp_ch_buf,
+ "%s: request exceed WFx capability: %zu > %d\n", __func__,
+ len, wdev->hw_caps.size_inp_ch_buf);
+ len = wdev->hwbus_ops->align_size(wdev->hwbus_priv, len);
+ ret = wfx_data_write(wdev, data, len);
+ if (ret)
+ goto end;
+
+ wdev->hif.tx_buffers_used++;
+end:
+ if (is_encrypted)
+ kfree(data);
+}
+
+static int bh_work_tx(struct wfx_dev *wdev, int max_msg)
+{
+ struct hif_msg *hif;
+ int i;
+
+ for (i = 0; i < max_msg; i++) {
+ hif = NULL;
+ if (wdev->hif.tx_buffers_used < wdev->hw_caps.num_inp_ch_bufs) {
+ /* FIXME: get queued data */
+ }
+ if (!hif)
+ return i;
+ tx_helper(wdev, hif);
+ }
+ return i;
+}
+
+/* In SDIO mode, it is necessary to make an access to a register to acknowledge
+ * last received message. It could be possible to restrict this acknowledge to
+ * SDIO mode and only if last operation was rx.
+ */
+static void ack_sdio_data(struct wfx_dev *wdev)
+{
+ uint32_t cfg_reg;
+
+ config_reg_read(wdev, &cfg_reg);
+ if (cfg_reg & 0xFF) {
+ dev_warn(wdev->dev, "chip reports errors: %02x\n", cfg_reg & 0xFF);
+ config_reg_write_bits(wdev, 0xFF, 0x00);
+ }
+}
+
+static void bh_work(struct work_struct *work)
+{
+ struct wfx_dev *wdev = container_of(work, struct wfx_dev, hif.bh);
+ int stats_req = 0, stats_cnf = 0, stats_ind = 0;
+ bool release_chip = false, last_op_is_rx = false;
+ int num_tx, num_rx;
+
+ device_wakeup(wdev);
+ do {
+ num_tx = bh_work_tx(wdev, 32);
+ stats_req += num_tx;
+ if (num_tx)
+ last_op_is_rx = false;
+ num_rx = bh_work_rx(wdev, 32, &stats_cnf);
+ stats_ind += num_rx;
+ if (num_rx)
+ last_op_is_rx = true;
+ } while (num_rx || num_tx);
+ stats_ind -= stats_cnf;
+
+ if (last_op_is_rx)
+ ack_sdio_data(wdev);
+ if (!wdev->hif.tx_buffers_used && !work_pending(work)) {
+ device_release(wdev);
+ release_chip = true;
+ }
+}
+
+/*
+ * An IRQ from chip did occur
+ */
+void wfx_bh_request_rx(struct wfx_dev *wdev)
+{
+ u32 cur, prev;
+
+ control_reg_read(wdev, &cur);
+ prev = atomic_xchg(&wdev->hif.ctrl_reg, cur);
+ complete(&wdev->hif.ctrl_ready);
+ queue_work(system_highpri_wq, &wdev->hif.bh);
+
+ if (!(cur & CTRL_NEXT_LEN_MASK))
+ dev_err(wdev->dev, "unexpected control register value: length field is 0: %04x\n",
+ cur);
+ if (prev != 0)
+ dev_err(wdev->dev, "received IRQ but previous data was not (yet) read: %04x/%04x\n",
+ prev, cur);
+}
+
+/*
+ * Driver want to send data
+ */
+void wfx_bh_request_tx(struct wfx_dev *wdev)
+{
+ queue_work(system_highpri_wq, &wdev->hif.bh);
+}
+
+void wfx_bh_register(struct wfx_dev *wdev)
+{
+ INIT_WORK(&wdev->hif.bh, bh_work);
+ init_completion(&wdev->hif.ctrl_ready);
+ init_waitqueue_head(&wdev->hif.tx_buffers_empty);
+}
+
+void wfx_bh_unregister(struct wfx_dev *wdev)
+{
+ flush_work(&wdev->hif.bh);
+}
projects / linux.git / commitdiff