From c774326a219536ab615d68a22875673f6f608b62 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 2 Mar 2017 15:50:56 -0800 Subject: [PATCH] Input: psmouse - introduce notion of SMBus companions Prepare PS/2 mouse drivers to work with devices that are accessible both via PS/2 and SMBus, which provides higher bandwidth, and thus suits better for modern multi-touch devices. We expect that SMBus drivers will take control over the device, so when we detect SMBus "protocol" we forego registering input device, or enabling PS/2 device reports (as it usually makes device unresponsive to access over SMBus). Reviewed-by: Benjamin Tissoires Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/psmouse-base.c | 103 ++++++++++++++++++++--------- drivers/input/mouse/psmouse.h | 1 + 2 files changed, 71 insertions(+), 33 deletions(-) diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c index bb5d164849ea..a84f8ed2ba5d 100644 --- a/drivers/input/mouse/psmouse-base.c +++ b/drivers/input/mouse/psmouse-base.c @@ -1424,9 +1424,8 @@ static void psmouse_cleanup(struct serio *serio) */ static void psmouse_disconnect(struct serio *serio) { - struct psmouse *psmouse, *parent = NULL; - - psmouse = serio_get_drvdata(serio); + struct psmouse *psmouse = serio_get_drvdata(serio); + struct psmouse *parent = NULL; sysfs_remove_group(&serio->dev.kobj, &psmouse_attribute_group); @@ -1454,7 +1453,10 @@ static void psmouse_disconnect(struct serio *serio) serio_close(serio); serio_set_drvdata(serio, NULL); - input_unregister_device(psmouse->dev); + + if (psmouse->dev) + input_unregister_device(psmouse->dev); + kfree(psmouse); if (parent) @@ -1575,12 +1577,18 @@ static int psmouse_connect(struct serio *serio, struct serio_driver *drv) psmouse_switch_protocol(psmouse, NULL); - psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); - psmouse_initialize(psmouse); + if (!psmouse->protocol->smbus_companion) { + psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); + psmouse_initialize(psmouse); - error = input_register_device(psmouse->dev); - if (error) - goto err_protocol_disconnect; + error = input_register_device(input_dev); + if (error) + goto err_protocol_disconnect; + } else { + /* Smbus companion will be reporting events, not us. */ + input_free_device(input_dev); + psmouse->dev = input_dev = NULL; + } if (parent && parent->pt_activate) parent->pt_activate(parent); @@ -1589,7 +1597,12 @@ static int psmouse_connect(struct serio *serio, struct serio_driver *drv) if (error) goto err_pt_deactivate; - psmouse_activate(psmouse); + /* + * PS/2 devices having SMBus companions should stay disabled + * on PS/2 side, in order to have SMBus part operable. + */ + if (!psmouse->protocol->smbus_companion) + psmouse_activate(psmouse); out: /* If this is a pass-through port the parent needs to be re-activated */ @@ -1602,8 +1615,10 @@ static int psmouse_connect(struct serio *serio, struct serio_driver *drv) err_pt_deactivate: if (parent && parent->pt_deactivate) parent->pt_deactivate(parent); - input_unregister_device(psmouse->dev); - input_dev = NULL; /* so we don't try to free it below */ + if (input_dev) { + input_unregister_device(input_dev); + input_dev = NULL; /* so we don't try to free it below */ + } err_protocol_disconnect: if (psmouse->disconnect) psmouse->disconnect(psmouse); @@ -1665,14 +1680,21 @@ static int __psmouse_reconnect(struct serio *serio, bool fast_reconnect) * OK, the device type (and capabilities) match the old one, * we can continue using it, complete initialization */ - psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); - - psmouse_initialize(psmouse); + if (!psmouse->protocol->smbus_companion) { + psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); + psmouse_initialize(psmouse); + } if (parent && parent->pt_activate) parent->pt_activate(parent); - psmouse_activate(psmouse); + /* + * PS/2 devices having SMBus companions should stay disabled + * on PS/2 side, in order to have SMBus part operable. + */ + if (!psmouse->protocol->smbus_companion) + psmouse_activate(psmouse); + rc = 0; out: @@ -1732,9 +1754,11 @@ ssize_t psmouse_attr_show_helper(struct device *dev, struct device_attribute *de { struct serio *serio = to_serio_port(dev); struct psmouse_attribute *attr = to_psmouse_attr(devattr); - struct psmouse *psmouse; + struct psmouse *psmouse = serio_get_drvdata(serio); - psmouse = serio_get_drvdata(serio); + if (psmouse->protocol->smbus_companion && + devattr != &psmouse_attr_protocol.dattr) + return -ENOENT; return attr->show(psmouse, attr->data, buf); } @@ -1753,6 +1777,12 @@ ssize_t psmouse_attr_set_helper(struct device *dev, struct device_attribute *dev psmouse = serio_get_drvdata(serio); + if (psmouse->protocol->smbus_companion && + devattr != &psmouse_attr_protocol.dattr) { + retval = -ENOENT; + goto out_unlock; + } + if (attr->protect) { if (psmouse->state == PSMOUSE_IGNORE) { retval = -ENODEV; @@ -1764,13 +1794,14 @@ ssize_t psmouse_attr_set_helper(struct device *dev, struct device_attribute *dev psmouse_deactivate(parent); } - psmouse_deactivate(psmouse); + if (!psmouse->protocol->smbus_companion) + psmouse_deactivate(psmouse); } retval = attr->set(psmouse, attr->data, buf, count); if (attr->protect) { - if (retval != -ENODEV) + if (retval != -ENODEV && !psmouse->protocol->smbus_companion) psmouse_activate(psmouse); if (parent) @@ -1879,23 +1910,29 @@ static ssize_t psmouse_attr_set_protocol(struct psmouse *psmouse, void *data, co psmouse_initialize(psmouse); psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); - error = input_register_device(psmouse->dev); - if (error) { - if (psmouse->disconnect) - psmouse->disconnect(psmouse); + if (psmouse->protocol->smbus_companion) { + input_free_device(psmouse->dev); + psmouse->dev = NULL; + } else { + error = input_register_device(psmouse->dev); + if (error) { + if (psmouse->disconnect) + psmouse->disconnect(psmouse); - psmouse_set_state(psmouse, PSMOUSE_IGNORE); - input_free_device(new_dev); - psmouse->dev = old_dev; - psmouse_set_state(psmouse, PSMOUSE_INITIALIZING); - psmouse_switch_protocol(psmouse, old_proto); - psmouse_initialize(psmouse); - psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); + psmouse_set_state(psmouse, PSMOUSE_IGNORE); + input_free_device(new_dev); + psmouse->dev = old_dev; + psmouse_set_state(psmouse, PSMOUSE_INITIALIZING); + psmouse_switch_protocol(psmouse, old_proto); + psmouse_initialize(psmouse); + psmouse_set_state(psmouse, PSMOUSE_CMD_MODE); - return error; + return error; + } } - input_unregister_device(old_dev); + if (old_dev) + input_unregister_device(old_dev); if (parent && parent->pt_activate) parent->pt_activate(parent); diff --git a/drivers/input/mouse/psmouse.h b/drivers/input/mouse/psmouse.h index 36bd42179456..e853dee05e79 100644 --- a/drivers/input/mouse/psmouse.h +++ b/drivers/input/mouse/psmouse.h @@ -76,6 +76,7 @@ struct psmouse_protocol { bool maxproto; bool ignore_parity; /* Protocol should ignore parity errors from KBC */ bool try_passthru; /* Try protocol also on passthrough ports */ + bool smbus_companion; /* "Protocol" is a stub, device is on SMBus */ const char *name; const char *alias; int (*detect)(struct psmouse *, bool); -- 2.20.1