Re: [PATCH] i2c: Mark instantiated device nodes with OF_POPULATE
From: Guenter Roeck <hidden>
Date: 2015-01-15 18:55:45
Also in:
linux-i2c
On Thu, Jan 15, 2015 at 08:33:18PM +0200, Pantelis Antoniou wrote:
quoted hunk
Mark (and unmark) device nodes with the POPULATE flag as appropriate. This is required to avoid multi probing when using I2C and device overlays containing a mux. This patch is also more careful with the release of the adapter device which caused a deadlock with muxes, and does not break the build on !OF since the node flag accessors are not defined then. Signed-off-by: Pantelis Antoniou <pantelis.antoniou-OWPKS81ov/FWk0Htik3J/w@public.gmane.org> --- drivers/i2c/i2c-core.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-)diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 39d25a8..1d44e3a 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c@@ -1122,6 +1122,10 @@ EXPORT_SYMBOL_GPL(i2c_new_device); */ void i2c_unregister_device(struct i2c_client *client) { +#if IS_ENABLED(CONFIG_OF_DYNAMIC)
Hi Pantelis, I thought I read a note somewhere a couple of days ago suggesting that CONFIG_OF_DYNAMIC would go away soon. Also, of_node_clear_flag is defined in #ifdef CONFIG_OF, and AFAICS none of the other callers set OF_POPULATED in the context of CONFIG_OF_DYNAMIC. Given that, wouldn't it be better to use CONFIG_OF ? Thanks, Guenter
quoted hunk
+ if (client->dev.of_node) + of_node_clear_flag(client->dev.of_node, OF_POPULATED); +#endif device_unregister(&client->dev); } EXPORT_SYMBOL_GPL(i2c_unregister_device);@@ -1441,8 +1445,11 @@ static void of_i2c_register_devices(struct i2c_adapter *adap) dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); - for_each_available_child_of_node(adap->dev.of_node, node) + for_each_available_child_of_node(adap->dev.of_node, node) { + if (of_node_test_and_set_flag(node, OF_POPULATED)) + continue; of_i2c_register_device(adap, node); + } } static int of_dev_node_match(struct device *dev, void *data)@@ -1976,6 +1983,11 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action, if (adap == NULL) return NOTIFY_OK; /* not for us */ + if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { + put_device(&adap->dev); + return NOTIFY_OK; + } + client = of_i2c_register_device(adap, rd->dn); put_device(&adap->dev);@@ -1986,6 +1998,10 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action, } break; case OF_RECONFIG_CHANGE_REMOVE: + /* already depopulated? */ + if (!of_node_check_flag(rd->dn, OF_POPULATED)) + return NOTIFY_OK; + /* find our device by node */ client = of_find_i2c_device_by_node(rd->dn); if (client == NULL)-- 1.7.12