From a9e3760b0838299649c0d57cca44daaf40ba3c33 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 14 Sep 2026 22:12:34 -1000 Subject: sched_ext: Maintain an online cid mask in the scheduler arena Schedulers on the default cid mapping treat [0, nr_online_cids) as the online set and restart on hotplug. Schedulers that install their own mapping with scx_bpf_cid_override() have no way to learn which cids are online: the count no longer identifies members and the CPU-form cpumask is unusable from cid programs. This is an obvious hole in the cid API. Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's arena, allocated alongside the per-CPU scratch masks and populated after the cid mapping is finalized and before ops.init(), for child schedulers too. The pointer stays valid through ops.exit() with no reference to take. It is the arena offset as a void pointer, the same form struct_ops arena arguments arrive in. The verifier types the void return as a scalar for the program's arena cast. The mask follows the SCX hotplug notifications: seeded from cpu_active_mask and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask only inside a hotplug transition. Updates walk the scheduler list under the lock that also serializes unlinking. Reads are live, not atomic snapshots. Root initialization excludes hotplug. v2: Reworded the getter kerneldoc (Andrea Righi). Signed-off-by: Tejun Heo Reviewed-by: Andrea Righi --- drivers/input/touchscreen/elo.c | 406 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 406 insertions(+) create mode 100644 drivers/input/touchscreen/elo.c (limited to 'drivers/input/touchscreen/elo.c') diff --git a/drivers/input/touchscreen/elo.c b/drivers/input/touchscreen/elo.c new file mode 100644 index 000000000..6814d5789 --- /dev/null +++ b/drivers/input/touchscreen/elo.c @@ -0,0 +1,406 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Elo serial touchscreen driver + * + * Copyright (c) 2004 Vojtech Pavlik + */ + + +/* + * This driver can handle serial Elo touchscreens using either the Elo standard + * 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo + * legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Elo serial touchscreen driver" + +MODULE_AUTHOR("Vojtech Pavlik "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define ELO_MAX_LENGTH 10 + +#define ELO10_PACKET_LEN 8 +#define ELO10_TOUCH 0x03 +#define ELO10_PRESSURE 0x80 + +#define ELO10_LEAD_BYTE 'U' + +#define ELO10_ID_CMD 'i' + +#define ELO10_TOUCH_PACKET 'T' +#define ELO10_ACK_PACKET 'A' +#define ELI10_ID_PACKET 'I' + +/* + * Per-touchscreen data. + */ + +struct elo { + struct input_dev *dev; + struct serio *serio; + struct mutex cmd_mutex; + struct completion cmd_done; + int id; + int idx; + unsigned char expected_packet; + unsigned char csum; + unsigned char data[ELO_MAX_LENGTH]; + unsigned char response[ELO10_PACKET_LEN]; + char phys[32]; +}; + +static void elo_process_data_10(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + case 0: + elo->csum = 0xaa; + if (data != ELO10_LEAD_BYTE) { + dev_dbg(&elo->serio->dev, + "unsynchronized data: 0x%02x\n", data); + elo->idx = 0; + } + break; + + case 9: + elo->idx = 0; + if (data != elo->csum) { + dev_dbg(&elo->serio->dev, + "bad checksum: 0x%02x, expected 0x%02x\n", + data, elo->csum); + break; + } + if (elo->data[1] != elo->expected_packet) { + if (elo->data[1] != ELO10_TOUCH_PACKET) + dev_dbg(&elo->serio->dev, + "unexpected packet: 0x%02x\n", + elo->data[1]); + break; + } + if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) { + input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]); + input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]); + if (elo->data[2] & ELO10_PRESSURE) + input_report_abs(dev, ABS_PRESSURE, + (elo->data[8] << 8) | elo->data[7]); + input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH); + input_sync(dev); + } else if (elo->data[1] == ELO10_ACK_PACKET) { + if (elo->data[2] == '0') + elo->expected_packet = ELO10_TOUCH_PACKET; + complete(&elo->cmd_done); + } else { + memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN); + elo->expected_packet = ELO10_ACK_PACKET; + } + break; + } + elo->csum += data; +} + +static void elo_process_data_6(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + + case 0: + if ((data & 0xc0) != 0xc0) + elo->idx = 0; + break; + + case 1: + if ((data & 0xc0) != 0x80) + elo->idx = 0; + break; + + case 2: + if ((data & 0xc0) != 0x40) + elo->idx = 0; + break; + + case 3: + if (data & 0xc0) { + elo->idx = 0; + break; + } + + input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f)); + input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f)); + + if (elo->id == 2) { + input_report_key(dev, BTN_TOUCH, 1); + input_sync(dev); + elo->idx = 0; + } + + break; + + case 4: + if (data) { + input_sync(dev); + elo->idx = 0; + } + break; + + case 5: + if ((data & 0xf0) == 0) { + input_report_abs(dev, ABS_PRESSURE, elo->data[5]); + input_report_key(dev, BTN_TOUCH, !!elo->data[5]); + } + input_sync(dev); + elo->idx = 0; + break; + } +} + +static void elo_process_data_3(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + + case 0: + if ((data & 0x7f) != 0x01) + elo->idx = 0; + break; + case 2: + input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80)); + input_report_abs(dev, ABS_X, elo->data[1]); + input_report_abs(dev, ABS_Y, elo->data[2]); + input_sync(dev); + elo->idx = 0; + break; + } +} + +static irqreturn_t elo_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct elo *elo = serio_get_drvdata(serio); + + switch (elo->id) { + case 0: + elo_process_data_10(elo, data); + break; + + case 1: + case 2: + elo_process_data_6(elo, data); + break; + + case 3: + elo_process_data_3(elo, data); + break; + } + + return IRQ_HANDLED; +} + +static int elo_command_10(struct elo *elo, unsigned char *packet) +{ + int error; + int i; + unsigned char csum = 0xaa + ELO10_LEAD_BYTE; + + guard(mutex)(&elo->cmd_mutex); + + scoped_guard(serio_pause_rx, elo->serio) { + elo->expected_packet = toupper(packet[0]); + init_completion(&elo->cmd_done); + } + + error = serio_write(elo->serio, ELO10_LEAD_BYTE); + if (error) + return error; + + for (i = 0; i < ELO10_PACKET_LEN; i++) { + csum += packet[i]; + error = serio_write(elo->serio, packet[i]); + if (error) + return error; + } + + error = serio_write(elo->serio, csum); + if (error) + return error; + + wait_for_completion_timeout(&elo->cmd_done, HZ); + + if (elo->expected_packet != ELO10_TOUCH_PACKET) + return -EIO; + + /* We are back in reporting mode, the command was ACKed */ + memcpy(packet, elo->response, ELO10_PACKET_LEN); + return 0; +} + +static int elo_setup_10(struct elo *elo) +{ + static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" }; + struct input_dev *dev = elo->dev; + unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD }; + + if (elo_command_10(elo, packet)) + return -1; + + dev->id.version = (packet[5] << 8) | packet[4]; + + input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0); + input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0); + if (packet[3] & ELO10_PRESSURE) + input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0); + + dev_info(&elo->serio->dev, + "%sTouch touchscreen, fw: %02x.%02x, features: 0x%02x, controller: 0x%02x\n", + elo_types[(packet[1] -'0') & 0x03], + packet[5], packet[4], packet[3], packet[7]); + + return 0; +} + +/* + * elo_disconnect() is the opposite of elo_connect() + */ + +static void elo_disconnect(struct serio *serio) +{ + struct elo *elo = serio_get_drvdata(serio); + + input_get_device(elo->dev); + input_unregister_device(elo->dev); + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_put_device(elo->dev); + kfree(elo); +} + +/* + * elo_connect() is the routine that is called when someone adds a + * new serio device that supports Gunze protocol and registers it as + * an input device. + */ + +static int elo_connect(struct serio *serio, struct serio_driver *drv) +{ + struct elo *elo; + struct input_dev *input_dev; + int err; + + elo = kzalloc_obj(*elo); + input_dev = input_allocate_device(); + if (!elo || !input_dev) { + err = -ENOMEM; + goto fail1; + } + + elo->serio = serio; + elo->id = serio->id.id; + elo->dev = input_dev; + elo->expected_packet = ELO10_TOUCH_PACKET; + mutex_init(&elo->cmd_mutex); + init_completion(&elo->cmd_done); + scnprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys); + + input_dev->name = "Elo Serial TouchScreen"; + input_dev->phys = elo->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_ELO; + input_dev->id.product = elo->id; + input_dev->id.version = 0x0100; + input_dev->dev.parent = &serio->dev; + + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + + serio_set_drvdata(serio, elo); + err = serio_open(serio, drv); + if (err) + goto fail2; + + switch (elo->id) { + + case 0: /* 10-byte protocol */ + if (elo_setup_10(elo)) { + err = -EIO; + goto fail3; + } + + break; + + case 1: /* 6-byte protocol */ + input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0); + fallthrough; + + case 2: /* 4-byte protocol */ + input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0); + break; + + case 3: /* 3-byte protocol */ + input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0); + break; + } + + err = input_register_device(elo->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(elo); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id elo_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_ELO, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, elo_serio_ids); + +static struct serio_driver elo_drv = { + .driver = { + .name = "elo", + }, + .description = DRIVER_DESC, + .id_table = elo_serio_ids, + .interrupt = elo_interrupt, + .connect = elo_connect, + .disconnect = elo_disconnect, +}; + +module_serio_driver(elo_drv); -- cgit v1.3.1