[PATCH 06/17] soc: fsl: cpm1: qmc: Add support for child devices

Herve Codina
2023-11-28T14:08:53Z

QMC child devices support is needed to avoid orphan DT nodes that use a
simple DT phandle to reference a QMC channel.

Allow to instantiate child devices and also extend the API to get the
qmc_chan using a child device.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
---
drivers/soc/fsl/qe/qmc.c | 91 +++++++++++++++++++++++++++++++---------
include/soc/fsl/qe/qmc.h | 2 +
2 files changed, 73 insertions(+), 20 deletions(-)

diff --git a/drivers/soc/fsl/qe/qmc.c b/drivers/soc/fsl/qe/qmc.c
index 27f2f16deac9..e716f13669a0 100644
--- a/drivers/soc/fsl/qe/qmc.c
+++ b/drivers/soc/fsl/qe/qmc.c
@@ -1425,8 +1425,16 @@ static int qmc_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, qmc);

+ /* Populate channel related devices */
+ ret = devm_of_platform_populate(qmc->dev);
+ if (ret)
+ goto err_disable_txrx;
+
return 0;

+err_disable_txrx:
+ qmc_setbits32(qmc->scc_regs + SCC_GSMRL, 0);
+
err_disable_intr:
qmc_write16(qmc->scc_regs + SCC_SCCM, 0);

@@ -1465,26 +1473,16 @@ static struct platform_driver qmc_driver = {
};
module_platform_driver(qmc_driver);

-struct qmc_chan *qmc_chan_get_byphandle(struct device_node *np, const char *phandle_name)
+static struct qmc_chan *qmc_chan_get_from_qmc(struct device_node *qmc_np, unsigned int chan_index)
{
- struct of_phandle_args out_args;
struct platform_device *pdev;
struct qmc_chan *qmc_chan;
struct qmc *qmc;
- int ret;

- ret = of_parse_phandle_with_fixed_args(np, phandle_name, 1, 0,
- &out_args);
- if (ret < 0)
- return ERR_PTR(ret);
-
- if (!of_match_node(qmc_driver.driver.of_match_table, out_args.np)) {
- of_node_put(out_args.np);
+ if (!of_match_node(qmc_driver.driver.of_match_table, qmc_np))
return ERR_PTR(-EINVAL);
- }

- pdev = of_find_device_by_node(out_args.np);
- of_node_put(out_args.np);
+ pdev = of_find_device_by_node(qmc_np);
if (!pdev)
return ERR_PTR(-ENODEV);

@@ -1494,17 +1492,12 @@ struct qmc_chan *qmc_chan_get_byphandle(struct device_node *np, const char *phan
return ERR_PTR(-EPROBE_DEFER);
}

- if (out_args.args_count != 1) {
+ if (chan_index >= ARRAY_SIZE(qmc->chans)) {
platform_device_put(pdev);
return ERR_PTR(-EINVAL);
}

- if (out_args.args[0] >= ARRAY_SIZE(qmc->chans)) {
- platform_device_put(pdev);
- return ERR_PTR(-EINVAL);
- }
-
- qmc_chan = qmc->chans[out_args.args[0]];
+ qmc_chan = qmc->chans[chan_index];
if (!qmc_chan) {
platform_device_put(pdev);
return ERR_PTR(-ENOENT);
@@ -1512,8 +1505,44 @@ struct qmc_chan *qmc_chan_get_byphandle(struct device_node *np, const char *phan

return qmc_chan;
}
+
+struct qmc_chan *qmc_chan_get_byphandle(struct device_node *np, const char *phandle_name)
+{
+ struct of_phandle_args out_args;
+ struct qmc_chan *qmc_chan;
+ int ret;
+
+ ret = of_parse_phandle_with_fixed_args(np, phandle_name, 1, 0,
+ &out_args);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ if (out_args.args_count != 1) {
+ of_node_put(out_args.np);
+ return ERR_PTR(-EINVAL);
+ }
+
+ qmc_chan = qmc_chan_get_from_qmc(out_args.np, out_args.args[0]);
+ of_node_put(out_args.np);
+ return qmc_chan;
+}
EXPORT_SYMBOL(qmc_chan_get_byphandle);

+struct qmc_chan *qmc_chan_get_bychild(struct device_node *np)
+{
+ struct device_node *qmc_np;
+ u32 chan_index;
+ int ret;
+
+ qmc_np = np->parent;
+ ret = of_property_read_u32(np, "reg", &chan_index);
+ if (ret)
+ return ERR_PTR(-EINVAL);
+
+ return qmc_chan_get_from_qmc(qmc_np, chan_index);
+}
+EXPORT_SYMBOL(qmc_chan_get_bychild);
+
void qmc_chan_put(struct qmc_chan *chan)
{
put_device(chan->qmc->dev);
@@ -1550,6 +1579,28 @@ struct qmc_chan *devm_qmc_chan_get_byphandle(struct device *dev,
}
EXPORT_SYMBOL(devm_qmc_chan_get_byphandle);

+struct qmc_chan *devm_qmc_chan_get_bychild(struct device *dev,
+ struct device_node *np)
+{
+ struct qmc_chan *qmc_chan;
+ struct qmc_chan **dr;
+
+ dr = devres_alloc(devm_qmc_chan_release, sizeof(*dr), GFP_KERNEL);
+ if (!dr)
+ return ERR_PTR(-ENOMEM);
+
+ qmc_chan = qmc_chan_get_bychild(np);
+ if (!IS_ERR(qmc_chan)) {
+ *dr = qmc_chan;
+ devres_add(dev, dr);
+ } else {
+ devres_free(dr);
+ }
+
+ return qmc_chan;
+}
+EXPORT_SYMBOL(devm_qmc_chan_get_bychild);
+
MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
MODULE_DESCRIPTION("CPM QMC driver");
MODULE_LICENSE("GPL");
diff --git a/include/soc/fsl/qe/qmc.h b/include/soc/fsl/qe/qmc.h
index 6f1d6cebc9fe..166484bb4294 100644
--- a/include/soc/fsl/qe/qmc.h
+++ b/include/soc/fsl/qe/qmc.h
@@ -17,9 +17,11 @@ struct device;
struct qmc_chan;

struct qmc_chan *qmc_chan_get_byphandle(struct device_node *np, const char *phandle_name);
+struct qmc_chan *qmc_chan_get_bychild(struct device_node *np);
void qmc_chan_put(struct qmc_chan *chan);
struct qmc_chan *devm_qmc_chan_get_byphandle(struct device *dev, struct device_node *np,
const char *phandle_name);
+struct qmc_chan *devm_qmc_chan_get_bychild(struct device *dev, struct device_node *np);

enum qmc_mode {
QMC_TRANSPARENT,
--
2.42.0