drm: dw_hdmi: use of_get_i2c_adapter_by_node interface
This change is needed to properly lock I2C bus driver, which serves
DDC.
The change fixes an overflow over zero of I2C bus driver user counter:
root@imx6q:~# lsmod
Not tainted
dw_hdmi_ahb_audio 4082 0 - Live 0xbf02c000
dw_hdmi_imx 3498 0 - Live 0xbf00d000
dw_hdmi 16398 2 dw_hdmi_ahb_audio,dw_hdmi_imx, Live 0xbf004000
i2c_imx 16687 0 - Live 0xbf017000
root@imx6q:~# rmmod dw_hdmi_imx
root@imx6q:~# lsmod
Not tainted
dw_hdmi_ahb_audio 4082 0 - Live 0xbf02c000
dw_hdmi 16398 1 dw_hdmi_ahb_audio, Live 0xbf004000
i2c_imx 16687 -1 - Live 0xbf017000
^^
root@imx6q:~# rmmod i2c_imx
rmmod: ERROR: Module i2c_imx is in use
Note that prior to this change put_device() coupled with
of_find_i2c_adapter_by_node() was missing on error path of
dw_hdmi_bind(), added i2c_put_adapter() there along with the change.
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 77ab473..ce3527c 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -1686,7 +1686,7 @@
ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0);
if (ddc_node) {
- hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
+ hdmi->ddc = of_get_i2c_adapter_by_node(ddc_node);
of_node_put(ddc_node);
if (!hdmi->ddc) {
dev_dbg(hdmi->dev, "failed to read ddc node\n");
@@ -1698,20 +1698,22 @@
}
hdmi->regs = devm_ioremap_resource(dev, iores);
- if (IS_ERR(hdmi->regs))
- return PTR_ERR(hdmi->regs);
+ if (IS_ERR(hdmi->regs)) {
+ ret = PTR_ERR(hdmi->regs);
+ goto err_res;
+ }
hdmi->isfr_clk = devm_clk_get(hdmi->dev, "isfr");
if (IS_ERR(hdmi->isfr_clk)) {
ret = PTR_ERR(hdmi->isfr_clk);
dev_err(hdmi->dev, "Unable to get HDMI isfr clk: %d\n", ret);
- return ret;
+ goto err_res;
}
ret = clk_prepare_enable(hdmi->isfr_clk);
if (ret) {
dev_err(hdmi->dev, "Cannot enable HDMI isfr clock: %d\n", ret);
- return ret;
+ goto err_res;
}
hdmi->iahb_clk = devm_clk_get(hdmi->dev, "iahb");
@@ -1797,6 +1799,8 @@
clk_disable_unprepare(hdmi->iahb_clk);
err_isfr:
clk_disable_unprepare(hdmi->isfr_clk);
+err_res:
+ i2c_put_adapter(hdmi->ddc);
return ret;
}