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path: root/drivers/i2c/muxes/i2c-mux-pca954x.c
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Diffstat (limited to 'drivers/i2c/muxes/i2c-mux-pca954x.c')
-rw-r--r--drivers/i2c/muxes/i2c-mux-pca954x.c141
1 files changed, 139 insertions, 2 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index bbf088e08d73..06fd9cc85b23 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -41,14 +41,20 @@
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/i2c/pca954x.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/of_irq.h>
#include <linux/pm.h>
#include <linux/slab.h>
+#include <linux/spinlock.h>
#define PCA954X_MAX_NCHANS 8
+#define PCA954X_IRQ_OFFSET 4
+
enum pca_type {
pca_9540,
pca_9542,
@@ -63,6 +69,7 @@ enum pca_type {
struct chip_desc {
u8 nchans;
u8 enable; /* used for muxes only */
+ u8 has_irq;
enum muxtype {
pca954x_ismux = 0,
pca954x_isswi
@@ -75,6 +82,10 @@ struct pca954x {
u8 last_chan; /* last register value */
u8 deselect;
struct i2c_client *client;
+
+ struct irq_domain *irq;
+ unsigned int irq_mask;
+ spinlock_t lock;
};
/* Provide specs for the PCA954x types we know about */
@@ -87,19 +98,23 @@ static const struct chip_desc chips[] = {
[pca_9542] = {
.nchans = 2,
.enable = 0x4,
+ .has_irq = 1,
.muxtype = pca954x_ismux,
},
[pca_9543] = {
.nchans = 2,
+ .has_irq = 1,
.muxtype = pca954x_isswi,
},
[pca_9544] = {
.nchans = 4,
.enable = 0x4,
+ .has_irq = 1,
.muxtype = pca954x_ismux,
},
[pca_9545] = {
.nchans = 4,
+ .has_irq = 1,
.muxtype = pca954x_isswi,
},
[pca_9547] = {
@@ -222,6 +237,114 @@ static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
return pca954x_reg_write(muxc->parent, client, data->last_chan);
}
+static irqreturn_t pca954x_irq_handler(int irq, void *dev_id)
+{
+ struct pca954x *data = dev_id;
+ unsigned int child_irq;
+ int ret, i, handled = 0;
+
+ ret = i2c_smbus_read_byte(data->client);
+ if (ret < 0)
+ return IRQ_NONE;
+
+ for (i = 0; i < data->chip->nchans; i++) {
+ if (ret & BIT(PCA954X_IRQ_OFFSET + i)) {
+ child_irq = irq_linear_revmap(data->irq, i);
+ handle_nested_irq(child_irq);
+ handled++;
+ }
+ }
+ return handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static void pca954x_irq_mask(struct irq_data *idata)
+{
+ struct pca954x *data = irq_data_get_irq_chip_data(idata);
+ unsigned int pos = idata->hwirq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ data->irq_mask &= ~BIT(pos);
+ if (!data->irq_mask)
+ disable_irq(data->client->irq);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static void pca954x_irq_unmask(struct irq_data *idata)
+{
+ struct pca954x *data = irq_data_get_irq_chip_data(idata);
+ unsigned int pos = idata->hwirq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ if (!data->irq_mask)
+ enable_irq(data->client->irq);
+ data->irq_mask |= BIT(pos);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static int pca954x_irq_set_type(struct irq_data *idata, unsigned int type)
+{
+ if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_LOW)
+ return -EINVAL;
+ return 0;
+}
+
+static struct irq_chip pca954x_irq_chip = {
+ .name = "i2c-mux-pca954x",
+ .irq_mask = pca954x_irq_mask,
+ .irq_unmask = pca954x_irq_unmask,
+ .irq_set_type = pca954x_irq_set_type,
+};
+
+static int pca954x_irq_setup(struct i2c_mux_core *muxc)
+{
+ struct pca954x *data = i2c_mux_priv(muxc);
+ struct i2c_client *client = data->client;
+ int c, err, irq;
+
+ if (!data->chip->has_irq || client->irq <= 0)
+ return 0;
+
+ spin_lock_init(&data->lock);
+
+ data->irq = irq_domain_add_linear(client->dev.of_node,
+ data->chip->nchans,
+ &irq_domain_simple_ops, data);
+ if (!data->irq)
+ return -ENODEV;
+
+ for (c = 0; c < data->chip->nchans; c++) {
+ irq = irq_create_mapping(data->irq, c);
+ irq_set_chip_data(irq, data);
+ irq_set_chip_and_handler(irq, &pca954x_irq_chip,
+ handle_simple_irq);
+ }
+
+ err = devm_request_threaded_irq(&client->dev, data->client->irq, NULL,
+ pca954x_irq_handler,
+ IRQF_ONESHOT | IRQF_SHARED,
+ "pca954x", data);
+ if (err)
+ goto err_req_irq;
+
+ disable_irq(data->client->irq);
+
+ return 0;
+err_req_irq:
+ for (c = 0; c < data->chip->nchans; c++) {
+ irq = irq_find_mapping(data->irq, c);
+ irq_dispose_mapping(irq);
+ }
+ irq_domain_remove(data->irq);
+
+ return err;
+}
+
/*
* I2C init/probing/exit functions
*/
@@ -286,6 +409,10 @@ static int pca954x_probe(struct i2c_client *client,
idle_disconnect_dt = of_node &&
of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
+ ret = pca954x_irq_setup(muxc);
+ if (ret)
+ goto fail_del_adapters;
+
/* Now create an adapter for each channel */
for (num = 0; num < data->chip->nchans; num++) {
bool idle_disconnect_pd = false;
@@ -311,7 +438,7 @@ static int pca954x_probe(struct i2c_client *client,
dev_err(&client->dev,
"failed to register multiplexed adapter"
" %d as bus %d\n", num, force);
- goto virt_reg_failed;
+ goto fail_del_adapters;
}
}
@@ -322,7 +449,7 @@ static int pca954x_probe(struct i2c_client *client,
return 0;
-virt_reg_failed:
+fail_del_adapters:
i2c_mux_del_adapters(muxc);
return ret;
}
@@ -330,6 +457,16 @@ virt_reg_failed:
static int pca954x_remove(struct i2c_client *client)
{
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
+ int c, irq;
+
+ if (data->irq) {
+ for (c = 0; c < data->chip->nchans; c++) {
+ irq = irq_find_mapping(data->irq, c);
+ irq_dispose_mapping(irq);
+ }
+ irq_domain_remove(data->irq);
+ }
i2c_mux_del_adapters(muxc);
return 0;