Lakka-LibreELEC/projects/Allwinner/patches/linux/0009-firmware-arm_scpi-Support-unidirectional-mailbox-cha.patch
2022-09-05 10:58:03 +00:00

123 lines
3.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel@sholland.org>
Date: Tue, 5 Mar 2019 22:02:41 -0600
Subject: [PATCH] firmware: arm_scpi: Support unidirectional mailbox channels
Some mailbox controllers have only unidirectional channels, so we need a
pair of them for each SCPI channel. If a mbox-names property is present,
look for "rx" and "tx" mbox channels; otherwise, the existing behavior
is preserved, and a single mbox channel is used for each SCPI channel.
Note that since the mailbox framework only supports a single phandle
with each name (mbox_request_channel_byname always returns the first
one), this new mode only supports a single SCPI channel.
Signed-off-by: Samuel Holland <samuel@sholland.org>
---
drivers/firmware/arm_scpi.c | 58 +++++++++++++++++++++++++++++--------
1 file changed, 46 insertions(+), 12 deletions(-)
--- a/drivers/firmware/arm_scpi.c
+++ b/drivers/firmware/arm_scpi.c
@@ -231,7 +231,8 @@ struct scpi_xfer {
struct scpi_chan {
struct mbox_client cl;
- struct mbox_chan *chan;
+ struct mbox_chan *rx_chan;
+ struct mbox_chan *tx_chan;
void __iomem *tx_payload;
void __iomem *rx_payload;
struct list_head rx_pending;
@@ -505,7 +506,7 @@ static int scpi_send_message(u8 idx, voi
msg->rx_len = rx_len;
reinit_completion(&msg->done);
- ret = mbox_send_message(scpi_chan->chan, msg);
+ ret = mbox_send_message(scpi_chan->tx_chan, msg);
if (ret < 0 || !rx_buf)
goto out;
@@ -856,8 +857,13 @@ static void scpi_free_channels(void *dat
struct scpi_drvinfo *info = data;
int i;
- for (i = 0; i < info->num_chans; i++)
- mbox_free_channel(info->channels[i].chan);
+ for (i = 0; i < info->num_chans; i++) {
+ struct scpi_chan *pchan = &info->channels[i];
+
+ if (pchan->tx_chan != pchan->rx_chan)
+ mbox_free_channel(pchan->tx_chan);
+ mbox_free_channel(pchan->rx_chan);
+ }
}
static int scpi_remove(struct platform_device *pdev)
@@ -913,6 +919,7 @@ static int scpi_probe(struct platform_de
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct scpi_drvinfo *scpi_drvinfo;
+ bool use_mbox_names = false;
scpi_drvinfo = devm_kzalloc(dev, sizeof(*scpi_drvinfo), GFP_KERNEL);
if (!scpi_drvinfo)
@@ -926,6 +933,14 @@ static int scpi_probe(struct platform_de
dev_err(dev, "no mboxes property in '%pOF'\n", np);
return -ENODEV;
}
+ if (of_get_property(dev->of_node, "mbox-names", NULL)) {
+ use_mbox_names = true;
+ if (count != 2) {
+ dev_err(dev, "need exactly 2 mboxes with mbox-names\n");
+ return -ENODEV;
+ }
+ count /= 2;
+ }
scpi_info->channels = devm_kcalloc(dev, count, sizeof(struct scpi_chan),
GFP_KERNEL);
@@ -974,15 +989,34 @@ static int scpi_probe(struct platform_de
mutex_init(&pchan->xfers_lock);
ret = scpi_alloc_xfer_list(dev, pchan);
- if (!ret) {
- pchan->chan = mbox_request_channel(cl, idx);
- if (!IS_ERR(pchan->chan))
- continue;
- ret = PTR_ERR(pchan->chan);
- if (ret != -EPROBE_DEFER)
- dev_err(dev, "failed to get channel%d err %d\n",
- idx, ret);
+ if (ret)
+ return ret;
+
+ if (use_mbox_names) {
+ pchan->rx_chan = mbox_request_channel_byname(cl, "rx");
+ if (IS_ERR(pchan->rx_chan)) {
+ ret = PTR_ERR(pchan->rx_chan);
+ goto fail;
+ }
+ pchan->tx_chan = mbox_request_channel_byname(cl, "tx");
+ if (IS_ERR(pchan->rx_chan)) {
+ ret = PTR_ERR(pchan->tx_chan);
+ goto fail;
+ }
+ } else {
+ pchan->rx_chan = mbox_request_channel(cl, idx);
+ if (IS_ERR(pchan->rx_chan)) {
+ ret = PTR_ERR(pchan->rx_chan);
+ goto fail;
+ }
+ pchan->tx_chan = pchan->rx_chan;
}
+ continue;
+
+fail:
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to get channel%d err %d\n",
+ idx, ret);
return ret;
}