1 // SPDX-License-Identifier: GPL-2.0
23  * - can go to sleep not earlier than after CR50_SLEEP_DELAY_MSEC.
24  * - needs up to CR50_WAKE_START_DELAY_USEC to wake after sleep.
25  * - requires waiting for "ready" IRQ, if supported; or waiting for at least
27  * - waits for up to CR50_FLOW_CONTROL for flow control 'ready' indication.
55 static inline struct cr50_spi_phy *to_cr50_spi_phy(struct tpm_tis_spi_phy *phy)  in to_cr50_spi_phy()  argument
57 	return container_of(phy, struct cr50_spi_phy, spi_phy);  in to_cr50_spi_phy()
69 	cr50_phy->irq_confirmed = true;  in cr50_spi_irq_handler()
70 	complete(&cr50_phy->spi_phy.ready);  in cr50_spi_irq_handler()
79 static void cr50_ensure_access_delay(struct cr50_spi_phy *phy)  in cr50_ensure_access_delay()  argument
81 	unsigned long allowed_access = phy->last_access + phy->access_delay;  in cr50_ensure_access_delay()
83 	struct device *dev = &phy->spi_phy.spi_device->dev;  in cr50_ensure_access_delay()
91 	if (time_in_range_open(time_now, phy->last_access, allowed_access)) {  in cr50_ensure_access_delay()
92 		unsigned long remaining, timeout = allowed_access - time_now;  in cr50_ensure_access_delay()
94 		remaining = wait_for_completion_timeout(&phy->spi_phy.ready,  in cr50_ensure_access_delay()
96 		if (!remaining && phy->irq_confirmed)  in cr50_ensure_access_delay()
100 	if (phy->irq_needs_confirmation) {  in cr50_ensure_access_delay()
101 		unsigned int attempt = ++phy->irq_confirmation_attempt;  in cr50_ensure_access_delay()
103 		if (phy->irq_confirmed) {  in cr50_ensure_access_delay()
104 			phy->irq_needs_confirmation = false;  in cr50_ensure_access_delay()
105 			phy->access_delay = CR50_READY_IRQ_TIMEOUT;  in cr50_ensure_access_delay()
109 			phy->irq_needs_confirmation = false;  in cr50_ensure_access_delay()
110 			dev_warn(dev, "IRQ not confirmed - will use delays\n");  in cr50_ensure_access_delay()
120 static bool cr50_needs_waking(struct cr50_spi_phy *phy)  in cr50_needs_waking()  argument
128 	return !time_in_range_open(jiffies, phy->last_access,  in cr50_needs_waking()
129 				   phy->spi_phy.wake_after);  in cr50_needs_waking()
134 	struct tpm_tis_spi_phy *phy = &cr50_phy->spi_phy;  in cr50_wake_if_needed()  local
145 		spi_sync_transfer(phy->spi_device, &spi_cs_wake, 1);  in cr50_wake_if_needed()
152 	phy->wake_after = jiffies + msecs_to_jiffies(CR50_SLEEP_DELAY_MSEC);  in cr50_wake_if_needed()
162 static int cr50_spi_flow_control(struct tpm_tis_spi_phy *phy,  in cr50_spi_flow_control()  argument
165 	struct device *dev = &phy->spi_device->dev;  in cr50_spi_flow_control()
167 	struct spi_message m;  in cr50_spi_flow_control()  local
170 	spi_xfer->len = 1;  in cr50_spi_flow_control()
173 		spi_message_init(&m);  in cr50_spi_flow_control()
174 		spi_message_add_tail(spi_xfer, &m);  in cr50_spi_flow_control()
175 		ret = spi_sync_locked(phy->spi_device, &m);  in cr50_spi_flow_control()
181 			return -EBUSY;  in cr50_spi_flow_control()
183 	} while (!(phy->iobuf[0] & 0x01));  in cr50_spi_flow_control()
194 	ret = device_property_read_u8(dev, "firmware-power-managed", &val);  in tpm_cr50_spi_is_firmware_power_managed()
204 	struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data);  in tpm_tis_spi_cr50_transfer()  local
205 	struct cr50_spi_phy *cr50_phy = to_cr50_spi_phy(phy);  in tpm_tis_spi_cr50_transfer()
208 	mutex_lock(&cr50_phy->time_track_mutex);  in tpm_tis_spi_cr50_transfer()
218 	cr50_phy->last_access = jiffies;  in tpm_tis_spi_cr50_transfer()
219 	mutex_unlock(&cr50_phy->time_track_mutex);  in tpm_tis_spi_cr50_transfer()
243 	struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data);  in cr50_print_fw_version()  local
252 	tpm_tis_write8(data, TPM_CR50_FW_VER(data->locality), 0);  in cr50_print_fw_version()
256 		tpm_tis_read_bytes(data, TPM_CR50_FW_VER(data->locality), 4,  in cr50_print_fw_version()
263 	dev_info(&phy->spi_device->dev, "Cr50 firmware version: %s\n", fw_ver);  in cr50_print_fw_version()
268 	struct tpm_tis_spi_phy *phy;  in cr50_spi_probe()  local
273 	cr50_phy = devm_kzalloc(&spi->dev, sizeof(*cr50_phy), GFP_KERNEL);  in cr50_spi_probe()
275 		return -ENOMEM;  in cr50_spi_probe()
277 	phy = &cr50_phy->spi_phy;  in cr50_spi_probe()
278 	phy->flow_control = cr50_spi_flow_control;  in cr50_spi_probe()
279 	phy->wake_after = jiffies;  in cr50_spi_probe()
280 	phy->priv.rng_quality = TPM_CR50_DEFAULT_RNG_QUALITY;  in cr50_spi_probe()
281 	init_completion(&phy->ready);  in cr50_spi_probe()
283 	cr50_phy->access_delay = CR50_NOIRQ_ACCESS_DELAY;  in cr50_spi_probe()
284 	cr50_phy->last_access = jiffies;  in cr50_spi_probe()
285 	mutex_init(&cr50_phy->time_track_mutex);  in cr50_spi_probe()
287 	if (spi->irq > 0) {  in cr50_spi_probe()
288 		ret = devm_request_irq(&spi->dev, spi->irq,  in cr50_spi_probe()
293 			if (ret == -EPROBE_DEFER)  in cr50_spi_probe()
295 			dev_warn(&spi->dev, "Requesting IRQ %d failed: %d\n",  in cr50_spi_probe()
296 				 spi->irq, ret);  in cr50_spi_probe()
308 			cr50_phy->irq_needs_confirmation = true;  in cr50_spi_probe()
311 		dev_warn(&spi->dev,  in cr50_spi_probe()
312 			 "No IRQ - will use delays between transactions.\n");  in cr50_spi_probe()
315 	ret = tpm_tis_spi_init(spi, phy, -1, &tpm_spi_cr50_phy_ops);  in cr50_spi_probe()
319 	cr50_print_fw_version(&phy->priv);  in cr50_spi_probe()
321 	chip = dev_get_drvdata(&spi->dev);  in cr50_spi_probe()
322 	if (tpm_cr50_spi_is_firmware_power_managed(&spi->dev))  in cr50_spi_probe()
323 		chip->flags |= TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED;  in cr50_spi_probe()
332 	struct tpm_tis_data *data = dev_get_drvdata(&chip->dev);  in tpm_tis_spi_resume()
333 	struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data);  in tpm_tis_spi_resume()  local
338 	phy->wake_after = jiffies;  in tpm_tis_spi_resume()