[PATCH v2 16/22] memory: tegra30-emc: Continue probing if timings are missing in device-tree

From: Dmitry Osipenko
Date: Sun Mar 29 2020 - 21:10:27 EST


EMC driver will become mandatory after turning it into interconnect
provider because interconnect users, like display controller driver, will
fail to probe using newer device-trees that have interconnect properties.
Thus make EMC driver to probe even if timings are missing in device-tree.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/memory/tegra/tegra30-emc.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/memory/tegra/tegra30-emc.c b/drivers/memory/tegra/tegra30-emc.c
index 900a291803ca..69698665d431 100644
--- a/drivers/memory/tegra/tegra30-emc.c
+++ b/drivers/memory/tegra/tegra30-emc.c
@@ -988,6 +988,11 @@ static struct device_node *emc_find_node_by_ram_code(struct device *dev)
u32 value, ram_code;
int err;

+ if (of_get_child_count(dev->of_node) == 0) {
+ dev_info(dev, "device-tree doesn't have memory timings\n");
+ return NULL;
+ }
+
ram_code = tegra_read_ram_code();

for_each_child_of_node(dev->of_node, np) {
@@ -1057,6 +1062,9 @@ static long emc_round_rate(unsigned long rate,
struct tegra_emc *emc = arg;
unsigned int i;

+ if (!emc->num_timings)
+ return clk_get_rate(emc->clk);
+
min_rate = min(min_rate, emc->timings[emc->num_timings - 1].rate);

for (i = 0; i < emc->num_timings; i++) {
@@ -1263,12 +1271,6 @@ static int tegra_emc_probe(struct platform_device *pdev)
struct tegra_emc *emc;
int err;

- if (of_get_child_count(pdev->dev.of_node) == 0) {
- dev_info(&pdev->dev,
- "device-tree node doesn't have memory timings\n");
- return -ENODEV;
- }
-
np = of_parse_phandle(pdev->dev.of_node, "nvidia,memory-controller", 0);
if (!np) {
dev_err(&pdev->dev, "could not get memory controller node\n");
@@ -1280,10 +1282,6 @@ static int tegra_emc_probe(struct platform_device *pdev)
if (!mc)
return -ENOENT;

- np = emc_find_node_by_ram_code(&pdev->dev);
- if (!np)
- return -EINVAL;
-
emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
if (!emc) {
of_node_put(np);
@@ -1297,10 +1295,13 @@ static int tegra_emc_probe(struct platform_device *pdev)
emc->clk_nb.notifier_call = emc_clk_change_notify;
emc->dev = &pdev->dev;

- err = emc_load_timings_from_dt(emc, np);
- of_node_put(np);
- if (err)
- return err;
+ np = emc_find_node_by_ram_code(&pdev->dev);
+ if (np) {
+ err = emc_load_timings_from_dt(emc, np);
+ of_node_put(np);
+ if (err)
+ return err;
+ }

emc->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(emc->regs))
--
2.25.1