summaryrefslogtreecommitdiffstats
path: root/drivers/mailbox/imx-mailbox.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/mailbox/imx-mailbox.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mailbox/imx-mailbox.c')
-rw-r--r--drivers/mailbox/imx-mailbox.c679
1 files changed, 679 insertions, 0 deletions
diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c
new file mode 100644
index 000000000..c5663398c
--- /dev/null
+++ b/drivers/mailbox/imx-mailbox.c
@@ -0,0 +1,679 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/firmware/imx/ipc.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_controller.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/suspend.h>
+#include <linux/slab.h>
+
+#define IMX_MU_xSR_GIPn(x) BIT(28 + (3 - (x)))
+#define IMX_MU_xSR_RFn(x) BIT(24 + (3 - (x)))
+#define IMX_MU_xSR_TEn(x) BIT(20 + (3 - (x)))
+#define IMX_MU_xSR_BRDIP BIT(9)
+
+/* General Purpose Interrupt Enable */
+#define IMX_MU_xCR_GIEn(x) BIT(28 + (3 - (x)))
+/* Receive Interrupt Enable */
+#define IMX_MU_xCR_RIEn(x) BIT(24 + (3 - (x)))
+/* Transmit Interrupt Enable */
+#define IMX_MU_xCR_TIEn(x) BIT(20 + (3 - (x)))
+/* General Purpose Interrupt Request */
+#define IMX_MU_xCR_GIRn(x) BIT(16 + (3 - (x)))
+
+#define IMX_MU_CHANS 16
+/* TX0/RX0/RXDB[0-3] */
+#define IMX_MU_SCU_CHANS 6
+#define IMX_MU_CHAN_NAME_SIZE 20
+
+enum imx_mu_chan_type {
+ IMX_MU_TYPE_TX, /* Tx */
+ IMX_MU_TYPE_RX, /* Rx */
+ IMX_MU_TYPE_TXDB, /* Tx doorbell */
+ IMX_MU_TYPE_RXDB, /* Rx doorbell */
+};
+
+struct imx_sc_rpc_msg_max {
+ struct imx_sc_rpc_msg hdr;
+ u32 data[7];
+};
+
+struct imx_mu_con_priv {
+ unsigned int idx;
+ char irq_desc[IMX_MU_CHAN_NAME_SIZE];
+ enum imx_mu_chan_type type;
+ struct mbox_chan *chan;
+ struct tasklet_struct txdb_tasklet;
+};
+
+struct imx_mu_priv {
+ struct device *dev;
+ void __iomem *base;
+ spinlock_t xcr_lock; /* control register lock */
+
+ struct mbox_controller mbox;
+ struct mbox_chan mbox_chans[IMX_MU_CHANS];
+
+ struct imx_mu_con_priv con_priv[IMX_MU_CHANS];
+ const struct imx_mu_dcfg *dcfg;
+ struct clk *clk;
+ int irq;
+ bool suspend;
+
+ u32 xcr;
+
+ bool side_b;
+};
+
+struct imx_mu_dcfg {
+ int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
+ int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
+ void (*init)(struct imx_mu_priv *priv);
+ u32 xTR[4]; /* Transmit Registers */
+ u32 xRR[4]; /* Receive Registers */
+ u32 xSR; /* Status Register */
+ u32 xCR; /* Control Register */
+};
+
+static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
+{
+ return container_of(mbox, struct imx_mu_priv, mbox);
+}
+
+static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
+{
+ iowrite32(val, priv->base + offs);
+}
+
+static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
+{
+ return ioread32(priv->base + offs);
+}
+
+static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, u32 set, u32 clr)
+{
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&priv->xcr_lock, flags);
+ val = imx_mu_read(priv, priv->dcfg->xCR);
+ val &= ~clr;
+ val |= set;
+ imx_mu_write(priv, val, priv->dcfg->xCR);
+ spin_unlock_irqrestore(&priv->xcr_lock, flags);
+
+ return val;
+}
+
+static int imx_mu_generic_tx(struct imx_mu_priv *priv,
+ struct imx_mu_con_priv *cp,
+ void *data)
+{
+ u32 *arg = data;
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_TX:
+ imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]);
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
+ break;
+ case IMX_MU_TYPE_TXDB:
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0);
+ tasklet_schedule(&cp->txdb_tasklet);
+ break;
+ default:
+ dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int imx_mu_generic_rx(struct imx_mu_priv *priv,
+ struct imx_mu_con_priv *cp)
+{
+ u32 dat;
+
+ dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]);
+ mbox_chan_received_data(cp->chan, (void *)&dat);
+
+ return 0;
+}
+
+static int imx_mu_scu_tx(struct imx_mu_priv *priv,
+ struct imx_mu_con_priv *cp,
+ void *data)
+{
+ struct imx_sc_rpc_msg_max *msg = data;
+ u32 *arg = data;
+ int i, ret;
+ u32 xsr;
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_TX:
+ /*
+ * msg->hdr.size specifies the number of u32 words while
+ * sizeof yields bytes.
+ */
+
+ if (msg->hdr.size > sizeof(*msg) / 4) {
+ /*
+ * The real message size can be different to
+ * struct imx_sc_rpc_msg_max size
+ */
+ dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on TX; got: %i bytes\n", sizeof(*msg), msg->hdr.size << 2);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < 4 && i < msg->hdr.size; i++)
+ imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
+ for (; i < msg->hdr.size; i++) {
+ ret = readl_poll_timeout(priv->base + priv->dcfg->xSR,
+ xsr,
+ xsr & IMX_MU_xSR_TEn(i % 4),
+ 0, 100);
+ if (ret) {
+ dev_err(priv->dev, "Send data index: %d timeout\n", i);
+ return ret;
+ }
+ imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
+ }
+
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
+ break;
+ default:
+ dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int imx_mu_scu_rx(struct imx_mu_priv *priv,
+ struct imx_mu_con_priv *cp)
+{
+ struct imx_sc_rpc_msg_max msg;
+ u32 *data = (u32 *)&msg;
+ int i, ret;
+ u32 xsr;
+
+ imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(0));
+ *data++ = imx_mu_read(priv, priv->dcfg->xRR[0]);
+
+ if (msg.hdr.size > sizeof(msg) / 4) {
+ dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on RX; got: %i bytes\n", sizeof(msg), msg.hdr.size << 2);
+ return -EINVAL;
+ }
+
+ for (i = 1; i < msg.hdr.size; i++) {
+ ret = readl_poll_timeout(priv->base + priv->dcfg->xSR, xsr,
+ xsr & IMX_MU_xSR_RFn(i % 4), 0, 100);
+ if (ret) {
+ dev_err(priv->dev, "timeout read idx %d\n", i);
+ return ret;
+ }
+ *data++ = imx_mu_read(priv, priv->dcfg->xRR[i % 4]);
+ }
+
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(0), 0);
+ mbox_chan_received_data(cp->chan, (void *)&msg);
+
+ return 0;
+}
+
+static void imx_mu_txdb_tasklet(unsigned long data)
+{
+ struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
+
+ mbox_chan_txdone(cp->chan, 0);
+}
+
+static irqreturn_t imx_mu_isr(int irq, void *p)
+{
+ struct mbox_chan *chan = p;
+ struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+ u32 val, ctrl;
+
+ ctrl = imx_mu_read(priv, priv->dcfg->xCR);
+ val = imx_mu_read(priv, priv->dcfg->xSR);
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_TX:
+ val &= IMX_MU_xSR_TEn(cp->idx) &
+ (ctrl & IMX_MU_xCR_TIEn(cp->idx));
+ break;
+ case IMX_MU_TYPE_RX:
+ val &= IMX_MU_xSR_RFn(cp->idx) &
+ (ctrl & IMX_MU_xCR_RIEn(cp->idx));
+ break;
+ case IMX_MU_TYPE_RXDB:
+ val &= IMX_MU_xSR_GIPn(cp->idx) &
+ (ctrl & IMX_MU_xCR_GIEn(cp->idx));
+ break;
+ default:
+ break;
+ }
+
+ if (!val)
+ return IRQ_NONE;
+
+ if (val == IMX_MU_xSR_TEn(cp->idx)) {
+ imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
+ mbox_chan_txdone(chan, 0);
+ } else if (val == IMX_MU_xSR_RFn(cp->idx)) {
+ priv->dcfg->rx(priv, cp);
+ } else if (val == IMX_MU_xSR_GIPn(cp->idx)) {
+ imx_mu_write(priv, IMX_MU_xSR_GIPn(cp->idx), priv->dcfg->xSR);
+ mbox_chan_received_data(chan, NULL);
+ } else {
+ dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
+ return IRQ_NONE;
+ }
+
+ if (priv->suspend)
+ pm_system_wakeup();
+
+ return IRQ_HANDLED;
+}
+
+static int imx_mu_send_data(struct mbox_chan *chan, void *data)
+{
+ struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+
+ return priv->dcfg->tx(priv, cp, data);
+}
+
+static int imx_mu_startup(struct mbox_chan *chan)
+{
+ struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+ unsigned long irq_flag = IRQF_SHARED;
+ int ret;
+
+ pm_runtime_get_sync(priv->dev);
+ if (cp->type == IMX_MU_TYPE_TXDB) {
+ /* Tx doorbell don't have ACK support */
+ tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
+ (unsigned long)cp);
+ return 0;
+ }
+
+ /* IPC MU should be with IRQF_NO_SUSPEND set */
+ if (!priv->dev->pm_domain)
+ irq_flag |= IRQF_NO_SUSPEND;
+
+ ret = request_irq(priv->irq, imx_mu_isr, irq_flag,
+ cp->irq_desc, chan);
+ if (ret) {
+ dev_err(priv->dev,
+ "Unable to acquire IRQ %d\n", priv->irq);
+ return ret;
+ }
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_RX:
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(cp->idx), 0);
+ break;
+ case IMX_MU_TYPE_RXDB:
+ imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIEn(cp->idx), 0);
+ break;
+ default:
+ break;
+ }
+
+ priv->suspend = true;
+
+ return 0;
+}
+
+static void imx_mu_shutdown(struct mbox_chan *chan)
+{
+ struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+
+ if (cp->type == IMX_MU_TYPE_TXDB) {
+ tasklet_kill(&cp->txdb_tasklet);
+ pm_runtime_put_sync(priv->dev);
+ return;
+ }
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_TX:
+ imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
+ break;
+ case IMX_MU_TYPE_RX:
+ imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(cp->idx));
+ break;
+ case IMX_MU_TYPE_RXDB:
+ imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_GIEn(cp->idx));
+ break;
+ default:
+ break;
+ }
+
+ free_irq(priv->irq, chan);
+ pm_runtime_put_sync(priv->dev);
+}
+
+static const struct mbox_chan_ops imx_mu_ops = {
+ .send_data = imx_mu_send_data,
+ .startup = imx_mu_startup,
+ .shutdown = imx_mu_shutdown,
+};
+
+static struct mbox_chan *imx_mu_scu_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *sp)
+{
+ u32 type, idx, chan;
+
+ if (sp->args_count != 2) {
+ dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
+ return ERR_PTR(-EINVAL);
+ }
+
+ type = sp->args[0]; /* channel type */
+ idx = sp->args[1]; /* index */
+
+ switch (type) {
+ case IMX_MU_TYPE_TX:
+ case IMX_MU_TYPE_RX:
+ if (idx != 0)
+ dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
+ chan = type;
+ break;
+ case IMX_MU_TYPE_RXDB:
+ chan = 2 + idx;
+ break;
+ default:
+ dev_err(mbox->dev, "Invalid chan type: %d\n", type);
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (chan >= mbox->num_chans) {
+ dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return &mbox->chans[chan];
+}
+
+static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *sp)
+{
+ u32 type, idx, chan;
+
+ if (sp->args_count != 2) {
+ dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
+ return ERR_PTR(-EINVAL);
+ }
+
+ type = sp->args[0]; /* channel type */
+ idx = sp->args[1]; /* index */
+ chan = type * 4 + idx;
+
+ if (chan >= mbox->num_chans) {
+ dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return &mbox->chans[chan];
+}
+
+static void imx_mu_init_generic(struct imx_mu_priv *priv)
+{
+ unsigned int i;
+
+ for (i = 0; i < IMX_MU_CHANS; i++) {
+ struct imx_mu_con_priv *cp = &priv->con_priv[i];
+
+ cp->idx = i % 4;
+ cp->type = i >> 2;
+ cp->chan = &priv->mbox_chans[i];
+ priv->mbox_chans[i].con_priv = cp;
+ snprintf(cp->irq_desc, sizeof(cp->irq_desc),
+ "imx_mu_chan[%i-%i]", cp->type, cp->idx);
+ }
+
+ priv->mbox.num_chans = IMX_MU_CHANS;
+ priv->mbox.of_xlate = imx_mu_xlate;
+
+ if (priv->side_b)
+ return;
+
+ /* Set default MU configuration */
+ imx_mu_write(priv, 0, priv->dcfg->xCR);
+}
+
+static void imx_mu_init_scu(struct imx_mu_priv *priv)
+{
+ unsigned int i;
+
+ for (i = 0; i < IMX_MU_SCU_CHANS; i++) {
+ struct imx_mu_con_priv *cp = &priv->con_priv[i];
+
+ cp->idx = i < 2 ? 0 : i - 2;
+ cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
+ cp->chan = &priv->mbox_chans[i];
+ priv->mbox_chans[i].con_priv = cp;
+ snprintf(cp->irq_desc, sizeof(cp->irq_desc),
+ "imx_mu_chan[%i-%i]", cp->type, cp->idx);
+ }
+
+ priv->mbox.num_chans = IMX_MU_SCU_CHANS;
+ priv->mbox.of_xlate = imx_mu_scu_xlate;
+
+ /* Set default MU configuration */
+ imx_mu_write(priv, 0, priv->dcfg->xCR);
+}
+
+static int imx_mu_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct imx_mu_priv *priv;
+ const struct imx_mu_dcfg *dcfg;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->irq = platform_get_irq(pdev, 0);
+ if (priv->irq < 0)
+ return priv->irq;
+
+ dcfg = of_device_get_match_data(dev);
+ if (!dcfg)
+ return -EINVAL;
+ priv->dcfg = dcfg;
+
+ priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk)) {
+ if (PTR_ERR(priv->clk) != -ENOENT)
+ return PTR_ERR(priv->clk);
+
+ priv->clk = NULL;
+ }
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret) {
+ dev_err(dev, "Failed to enable clock\n");
+ return ret;
+ }
+
+ priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
+
+ priv->dcfg->init(priv);
+
+ spin_lock_init(&priv->xcr_lock);
+
+ priv->mbox.dev = dev;
+ priv->mbox.ops = &imx_mu_ops;
+ priv->mbox.chans = priv->mbox_chans;
+ priv->mbox.txdone_irq = true;
+
+ platform_set_drvdata(pdev, priv);
+
+ ret = devm_mbox_controller_register(dev, &priv->mbox);
+ if (ret) {
+ clk_disable_unprepare(priv->clk);
+ return ret;
+ }
+
+ pm_runtime_enable(dev);
+
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(dev);
+ goto disable_runtime_pm;
+ }
+
+ ret = pm_runtime_put_sync(dev);
+ if (ret < 0)
+ goto disable_runtime_pm;
+
+ clk_disable_unprepare(priv->clk);
+
+ priv->suspend = false;
+
+ return 0;
+
+disable_runtime_pm:
+ pm_runtime_disable(dev);
+ clk_disable_unprepare(priv->clk);
+ return ret;
+}
+
+static int imx_mu_remove(struct platform_device *pdev)
+{
+ struct imx_mu_priv *priv = platform_get_drvdata(pdev);
+
+ pm_runtime_disable(priv->dev);
+
+ return 0;
+}
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
+ .tx = imx_mu_generic_tx,
+ .rx = imx_mu_generic_rx,
+ .init = imx_mu_init_generic,
+ .xTR = {0x0, 0x4, 0x8, 0xc},
+ .xRR = {0x10, 0x14, 0x18, 0x1c},
+ .xSR = 0x20,
+ .xCR = 0x24,
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
+ .tx = imx_mu_generic_tx,
+ .rx = imx_mu_generic_rx,
+ .init = imx_mu_init_generic,
+ .xTR = {0x20, 0x24, 0x28, 0x2c},
+ .xRR = {0x40, 0x44, 0x48, 0x4c},
+ .xSR = 0x60,
+ .xCR = 0x64,
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
+ .tx = imx_mu_scu_tx,
+ .rx = imx_mu_scu_rx,
+ .init = imx_mu_init_scu,
+ .xTR = {0x0, 0x4, 0x8, 0xc},
+ .xRR = {0x10, 0x14, 0x18, 0x1c},
+ .xSR = 0x20,
+ .xCR = 0x24,
+};
+
+static const struct of_device_id imx_mu_dt_ids[] = {
+ { .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
+ { .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
+ { .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
+ { },
+};
+MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
+
+static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
+{
+ struct imx_mu_priv *priv = dev_get_drvdata(dev);
+
+ if (!priv->clk)
+ priv->xcr = imx_mu_read(priv, priv->dcfg->xCR);
+
+ return 0;
+}
+
+static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
+{
+ struct imx_mu_priv *priv = dev_get_drvdata(dev);
+
+ /*
+ * ONLY restore MU when context lost, the TIE could
+ * be set during noirq resume as there is MU data
+ * communication going on, and restore the saved
+ * value will overwrite the TIE and cause MU data
+ * send failed, may lead to system freeze. This issue
+ * is observed by testing freeze mode suspend.
+ */
+ if (!imx_mu_read(priv, priv->dcfg->xCR) && !priv->clk)
+ imx_mu_write(priv, priv->xcr, priv->dcfg->xCR);
+
+ return 0;
+}
+
+static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
+{
+ struct imx_mu_priv *priv = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(priv->clk);
+
+ return 0;
+}
+
+static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
+{
+ struct imx_mu_priv *priv = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ dev_err(dev, "failed to enable clock\n");
+
+ return ret;
+}
+
+static const struct dev_pm_ops imx_mu_pm_ops = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
+ imx_mu_resume_noirq)
+ SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
+ imx_mu_runtime_resume, NULL)
+};
+
+static struct platform_driver imx_mu_driver = {
+ .probe = imx_mu_probe,
+ .remove = imx_mu_remove,
+ .driver = {
+ .name = "imx_mu",
+ .of_match_table = imx_mu_dt_ids,
+ .pm = &imx_mu_pm_ops,
+ },
+};
+module_platform_driver(imx_mu_driver);
+
+MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
+MODULE_DESCRIPTION("Message Unit driver for i.MX");
+MODULE_LICENSE("GPL v2");