On Wed, Jul 18, 2018 at 09:03:08PM +0530, Balakrishna Godavarthi wrote: > Hi Matthias, > > On 2018-07-16 21:35, Matthias Kaehlcke wrote: > > On Mon, Jul 16, 2018 at 07:21:56PM +0530, Balakrishna Godavarthi wrote: > > > Hi Matthias, > > > > > > On 2018-07-07 03:51, Matthias Kaehlcke wrote: > > > > On Thu, Jul 05, 2018 at 10:25:15PM +0530, Balakrishna Godavarthi wrote: > > > > > Add support to set voltage/current of various regulators > > > > > to power up/down Bluetooth chip wcn3990. > > > > > > > > > > Signed-off-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx> > > > > > --- > > > > > changes in v9: > > > > > * moved flow control to vendor and set_baudarte functions. > > > > > * removed parent regs. > > > > > > > > > > changes in v8: > > > > > * closing qca buffer, if qca_power_setup fails > > > > > * chnaged ibs start timer function call location. > > > > > * updated review comments. > > > > > > > > > > changes in v7: > > > > > * addressed review comments. > > > > > > > > > > changes in v6: > > > > > * Hooked up qca_power to qca_serdev. > > > > > * renamed all the naming inconsistency functions with qca_* > > > > > * leveraged common code of ROME for wcn3990. > > > > > * created wrapper functions for re-usable blocks. > > > > > * updated function of _*regulator_enable and _*regualtor_disable. > > > > > * removed redundant comments and functions. > > > > > * addressed review comments. > > > > > > > > > > Changes in v5: > > > > > * updated regulator vddpa min_uV to 1304000. > > > > > * addressed review comments. > > > > > > > > > > Changes in v4: > > > > > * Segregated the changes of btqca from hci_qca > > > > > * rebased all changes on top of bluetooth-next. > > > > > * addressed review comments. > > > > > > > > > > --- > > > > > drivers/bluetooth/btqca.h | 3 + > > > > > drivers/bluetooth/hci_qca.c | 387 > > > > > +++++++++++++++++++++++++++++++----- > > > > > 2 files changed, 345 insertions(+), 45 deletions(-) > > > > > > > > > > diff --git a/drivers/bluetooth/btqca.h b/drivers/bluetooth/btqca.h > > > > > index a9c2779f3e07..0c01f375fe83 100644 > > > > > --- a/drivers/bluetooth/btqca.h > > > > > +++ b/drivers/bluetooth/btqca.h > > > > > @@ -37,6 +37,9 @@ > > > > > #define EDL_TAG_ID_HCI (17) > > > > > #define EDL_TAG_ID_DEEP_SLEEP (27) > > > > > > > > > > +#define QCA_WCN3990_POWERON_PULSE 0xFC > > > > > +#define QCA_WCN3990_POWEROFF_PULSE 0xC0 > > > > > + > > > > > enum qca_bardrate { > > > > > QCA_BAUDRATE_115200 = 0, > > > > > QCA_BAUDRATE_57600, > > > > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > > > > > index 7ebfaa0edf3f..d62c7785a618 100644 > > > > > --- a/drivers/bluetooth/hci_qca.c > > > > > +++ b/drivers/bluetooth/hci_qca.c > > > > > @@ -5,7 +5,7 @@ > > > > > * protocol extension to H4. > > > > > * > > > > > * Copyright (C) 2007 Texas Instruments, Inc. > > > > > - * Copyright (c) 2010, 2012 The Linux Foundation. All rights > > > > > reserved. > > > > > + * Copyright (c) 2010, 2012, 2018 The Linux Foundation. All rights > > > > > reserved. > > > > > * > > > > > * Acknowledgements: > > > > > * This file is based on hci_ll.c, which was... > > > > > @@ -31,9 +31,14 @@ > > > > > #include <linux/kernel.h> > > > > > #include <linux/clk.h> > > > > > #include <linux/debugfs.h> > > > > > +#include <linux/delay.h> > > > > > +#include <linux/device.h> > > > > > #include <linux/gpio/consumer.h> > > > > > #include <linux/mod_devicetable.h> > > > > > #include <linux/module.h> > > > > > +#include <linux/of_device.h> > > > > > +#include <linux/platform_device.h> > > > > > +#include <linux/regulator/consumer.h> > > > > > #include <linux/serdev.h> > > > > > > > > > > #include <net/bluetooth/bluetooth.h> > > > > > @@ -124,12 +129,46 @@ enum qca_speed_type { > > > > > QCA_OPER_SPEED > > > > > }; > > > > > > > > > > +/* > > > > > + * Voltage regulator information required for configuring the > > > > > + * QCA Bluetooth chipset > > > > > + */ > > > > > +struct qca_vreg { > > > > > + const char *name; > > > > > + unsigned int min_uV; > > > > > + unsigned int max_uV; > > > > > + unsigned int load_uA; > > > > > +}; > > > > > + > > > > > +struct qca_vreg_data { > > > > > + enum qca_btsoc_type soc_type; > > > > > + struct qca_vreg *vregs; > > > > > + size_t num_vregs; > > > > > +}; > > > > > + > > > > > +/* > > > > > + * Platform data for the QCA Bluetooth power driver. > > > > > + */ > > > > > +struct qca_power { > > > > > + struct device *dev; > > > > > + const struct qca_vreg_data *vreg_data; > > > > > + struct regulator_bulk_data *vreg_bulk; > > > > > + bool vregs_on; > > > > > +}; > > > > > + > > > > > struct qca_serdev { > > > > > struct hci_uart serdev_hu; > > > > > struct gpio_desc *bt_en; > > > > > struct clk *susclk; > > > > > + enum qca_btsoc_type btsoc_type; > > > > > + struct qca_power *bt_power; > > > > > + u32 init_speed; > > > > > + u32 oper_speed; > > > > > }; > > > > > > > > > > +static int qca_power_setup(struct hci_uart *hu, bool on); > > > > > +static void qca_power_shutdown(struct hci_uart *hu); > > > > > + > > > > > static void __serial_clock_on(struct tty_struct *tty) > > > > > { > > > > > /* TODO: Some chipset requires to enable UART clock on client > > > > > @@ -407,6 +446,7 @@ static int qca_open(struct hci_uart *hu) > > > > > { > > > > > struct qca_serdev *qcadev; > > > > > struct qca_data *qca; > > > > > + int ret; > > > > > > > > > > BT_DBG("hu %p qca_open", hu); > > > > > > > > > > @@ -458,19 +498,32 @@ static int qca_open(struct hci_uart *hu) > > > > > > > > > > hu->priv = qca; > > > > > > > > > > - timer_setup(&qca->wake_retrans_timer, > > > > > hci_ibs_wake_retrans_timeout, 0); > > > > > - qca->wake_retrans = IBS_WAKE_RETRANS_TIMEOUT_MS; > > > > > - > > > > > - timer_setup(&qca->tx_idle_timer, hci_ibs_tx_idle_timeout, 0); > > > > > - qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS; > > > > > - > > > > > if (hu->serdev) { > > > > > serdev_device_open(hu->serdev); > > > > > > > > > > qcadev = serdev_device_get_drvdata(hu->serdev); > > > > > - gpiod_set_value_cansleep(qcadev->bt_en, 1); > > > > > + if (qcadev->btsoc_type != QCA_WCN3990) { > > > > > + gpiod_set_value_cansleep(qcadev->bt_en, 1); > > > > > + } else { > > > > > + hu->init_speed = qcadev->init_speed; > > > > > + hu->oper_speed = qcadev->oper_speed; > > > > > + ret = qca_power_setup(hu, true); > > > > > + if (ret) { > > > > > + destroy_workqueue(qca->workqueue); > > > > > + kfree_skb(qca->rx_skb); > > > > > + hu->priv = NULL; > > > > > + kfree(qca); > > > > > + return ret; > > > > > + } > > > > > + } > > > > > } > > > > > > > > > > + timer_setup(&qca->wake_retrans_timer, > > > > > hci_ibs_wake_retrans_timeout, 0); > > > > > + qca->wake_retrans = IBS_WAKE_RETRANS_TIMEOUT_MS; > > > > > + > > > > > + timer_setup(&qca->tx_idle_timer, hci_ibs_tx_idle_timeout, 0); > > > > > + qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS; > > > > > + > > > > > BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u", > > > > > qca->tx_idle_delay, qca->wake_retrans); > > > > > > > > > > @@ -554,10 +607,13 @@ static int qca_close(struct hci_uart *hu) > > > > > qca->hu = NULL; > > > > > > > > > > if (hu->serdev) { > > > > > - serdev_device_close(hu->serdev); > > > > > - > > > > > qcadev = serdev_device_get_drvdata(hu->serdev); > > > > > - gpiod_set_value_cansleep(qcadev->bt_en, 0); > > > > > + if (qcadev->btsoc_type == QCA_WCN3990) > > > > > + qca_power_shutdown(hu); > > > > > + else > > > > > + gpiod_set_value_cansleep(qcadev->bt_en, 0); > > > > > + > > > > > + serdev_device_close(hu->serdev); > > > > > } > > > > > > > > > > kfree_skb(qca->rx_skb); > > > > > @@ -891,6 +947,7 @@ static int qca_set_baudrate(struct hci_dev > > > > > *hdev, uint8_t baudrate) > > > > > struct hci_uart *hu = hci_get_drvdata(hdev); > > > > > struct qca_data *qca = hu->priv; > > > > > struct sk_buff *skb; > > > > > + struct qca_serdev *qcadev; > > > > > u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 }; > > > > > > > > > > if (baudrate > QCA_BAUDRATE_3200000) > > > > > @@ -904,6 +961,13 @@ static int qca_set_baudrate(struct hci_dev > > > > > *hdev, uint8_t baudrate) > > > > > return -ENOMEM; > > > > > } > > > > > > > > > > + /* Disabling hardware flow control is mandate while > > > > > > > > nit: s/mandate/mandatory|required/ > > > > > > > > > + * sending change baudrate request to wcn3990 SoC. > > > > > + */ > > > > > + qcadev = serdev_device_get_drvdata(hu->serdev); > > > > > + if (qcadev->btsoc_type == QCA_WCN3990) > > > > > + hci_uart_set_flow_control(hu, true); > > > > > + > > > > > /* Assign commands to change baudrate and packet type. */ > > > > > skb_put_data(skb, cmd, sizeof(cmd)); > > > > > hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; > > > > > @@ -919,6 +983,9 @@ static int qca_set_baudrate(struct hci_dev > > > > > *hdev, uint8_t baudrate) > > > > > schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS)); > > > > > set_current_state(TASK_RUNNING); > > > > > > > > > > + if (qcadev->btsoc_type == QCA_WCN3990) > > > > > + hci_uart_set_flow_control(hu, false); > > > > > + > > > > > return 0; > > > > > } > > > > > > > > > > @@ -930,6 +997,36 @@ static inline void host_set_baudrate(struct > > > > > hci_uart *hu, unsigned int speed) > > > > > hci_uart_set_baudrate(hu, speed); > > > > > } > > > > > > > > > > +static int qca_send_vendor_cmd(struct hci_dev *hdev, u8 cmd) > > > > > +{ > > > > > + struct hci_uart *hu = hci_get_drvdata(hdev); > > > > > + struct qca_data *qca = hu->priv; > > > > > + struct sk_buff *skb; > > > > > + > > > > > + bt_dev_dbg(hdev, "sending command %02x to SoC", cmd); > > > > > + > > > > > + skb = bt_skb_alloc(sizeof(cmd), GFP_KERNEL); > > > > > + if (!skb) > > > > > + return -ENOMEM; > > > > > + > > > > > + /* Disabling hardware flow control is mandate while > > > > > > > > Same nit as above > > > > > > > > > + * sending vendor power on and off pulse to SoC. > > > > > + */ > > > > > > > > The function is called qca_send_vendor_cmd(), the comment about power > > > > on/off pulses seems misplaced here. Are there other 'vendor commands' > > > > that require a different flow control behavior? > > > > > > > > Perhaps the function should have a different name or we need another > > > > wrapper. > > > > > > > > > + hci_uart_set_flow_control(hu, true); > > > > > > > > Should the changing of the flow control be limited to wcn3990? As of > > > > now the function is only called for wcn3990, however this is not > > > > stated as a requirement and might change in the future. > > > > > > > > > + skb_put_u8(skb, cmd); > > > > > + hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; > > > > > + > > > > > + skb_queue_tail(&qca->txq, skb); > > > > > + hci_uart_tx_wakeup(hu); > > > > > + > > > > > + /* Wait for 100 uS for SoC to settle down */ > > > > > + usleep_range(100, 200); > > > > > > > > Is this needed for any 'vendor command' or directly related with the > > > > power on/off pulses? > > > > > > > > > + hci_uart_set_flow_control(hu, false); > > > > > + > > > > > + return 0; > > > > > +} > > > > > + > > > > > static unsigned int qca_get_speed(struct hci_uart *hu, > > > > > enum qca_speed_type speed_type) > > > > > { > > > > > @@ -952,10 +1049,19 @@ static unsigned int qca_get_speed(struct > > > > > hci_uart *hu, > > > > > > > > > > static int qca_check_speeds(struct hci_uart *hu) > > > > > { > > > > > - /* One or the other speeds should be non zero. */ > > > > > - if (!qca_get_speed(hu, QCA_INIT_SPEED) && > > > > > - !qca_get_speed(hu, QCA_OPER_SPEED)) > > > > > + struct qca_serdev *qcadev; > > > > > + > > > > > + qcadev = serdev_device_get_drvdata(hu->serdev); > > > > > + if ((qcadev->btsoc_type == QCA_WCN3990 && > > > > > + !qca_get_speed(hu, QCA_INIT_SPEED)) || > > > > > + !qca_get_speed(hu, QCA_OPER_SPEED)) { > > > > > + /* Both INIT and OPER speed should be non zero. */ > > > > > return -EINVAL; > > > > > + } else if (!qca_get_speed(hu, QCA_INIT_SPEED) && > > > > > + !qca_get_speed(hu, QCA_OPER_SPEED)) { > > > > > + /* One or the other speeds should be non zero. */ > > > > > + return -EINVAL; > > > > > + } > > > > > > > > It is questionable if the comments are useful, they are basically > > > > stating the same as the conditions. > > > > > > > > if-else statements with a single statement in all branches shouldn't > > > > use curly braces. Personally I don't dislike them in this case with > > > > the multi-line conditions, but in principle they shoulnd't be there. > > > > > > > > nit: this would be easier to read with nested if statements: > > > > > > > > if (qcadev->btsoc_type == QCA_WCN3990) > > > > if (!qca_get_speed(hu, QCA_INIT_SPEED)) || > > > > !qca_get_speed(hu, QCA_OPER_SPEED)) > > > > return -EINVAL; > > > > else > > > > if (!qca_get_speed(hu, QCA_INIT_SPEED) && > > > > !qca_get_speed(hu, QCA_OPER_SPEED)) { > > > > return -EINVAL; > > > > > > > > > return 0; > > > > > } > > > > > @@ -986,15 +1092,40 @@ static int qca_set_speed(struct hci_uart *hu, > > > > > enum qca_speed_type speed_type) > > > > > return 0; > > > > > } > > > > > > > > > > +static int qca_wcn3990_init(struct hci_uart *hu) > > > > > +{ > > > > > + int ret; > > > > > + > > > > > + ret = qca_send_vendor_cmd(hu->hdev, QCA_WCN3990_POWERON_PULSE); > > > > > + if (ret) > > > > > + return ret; > > > > > + > > > > > + /* Wait for 100 ms for SoC to boot up */ > > > > > + msleep(100); > > > > > + serdev_device_close(hu->serdev); > > > > > + ret = serdev_device_open(hu->serdev); > > > > > + if (ret) { > > > > > + bt_dev_err(hu->hdev, "failed to open port"); > > > > > + return ret; > > > > > + } > > > > > + > > > > > + /* Setup initial baudrate */ > > > > > + qca_set_speed(hu, QCA_INIT_SPEED); > > > > > > > > The comment is a bit redundant. > > > > > > > > > + hci_uart_set_flow_control(hu, false); > > > > > + > > > > > + return 0; > > > > > +} > > > > > + > > > > > static int qca_setup(struct hci_uart *hu) > > > > > { > > > > > struct hci_dev *hdev = hu->hdev; > > > > > struct qca_data *qca = hu->priv; > > > > > unsigned int speed, qca_baudrate = QCA_BAUDRATE_115200; > > > > > + struct qca_serdev *qcadev; > > > > > int ret; > > > > > int soc_ver = 0; > > > > > > > > > > - bt_dev_info(hdev, "ROME setup"); > > > > > + qcadev = serdev_device_get_drvdata(hu->serdev); > > > > > > > > > > ret = qca_check_speeds(hu); > > > > > if (ret) > > > > > @@ -1006,6 +1137,21 @@ static int qca_setup(struct hci_uart *hu) > > > > > /* Setup initial baudrate */ > > > > > qca_set_speed(hu, QCA_INIT_SPEED); > > > > > > > > > > + if (qcadev->btsoc_type == QCA_WCN3990) { > > > > > + bt_dev_dbg(hdev, "setting up wcn3990"); > > > > > > > > Seems like this should be bt_dev_info() for consistency with Rome. > > > > > > > > > + ret = qca_wcn3990_init(hu); > > > > > + if (ret) > > > > > + return ret; > > > > > + > > > > > + ret = qca_read_soc_version(hdev, &soc_ver); > > > > > + if (ret < 0 || soc_ver == 0) { > > > > > + bt_dev_err(hdev, "Failed to get version %d", ret); > > > > > + return ret; > > > > > + } > > > > > + } else { > > > > > + bt_dev_info(hdev, "ROME setup"); > > > > > + } > > > > > + > > > > > /* Setup user speed if needed */ > > > > > speed = qca_get_speed(hu, QCA_OPER_SPEED); > > > > > if (speed) { > > > > > @@ -1016,16 +1162,18 @@ static int qca_setup(struct hci_uart *hu) > > > > > qca_baudrate = qca_get_baudrate_value(speed); > > > > > } > > > > > > > > > > - /* Get QCA version information */ > > > > > - ret = qca_read_soc_version(hdev, &soc_ver); > > > > > - if (ret < 0 || soc_ver == 0) { > > > > > - bt_dev_err(hdev, "QCA Failed to get version (%d)", ret); > > > > > - return ret; > > > > > + if (!soc_ver) { > > > > > > > > > > > > The following would probably be clearer: > > > > > > > > if (qcadev->btsoc_type != QCA_WCN3990) { > > > > > > > > > + /* Get QCA version information */ > > > > > + ret = qca_read_soc_version(hdev, &soc_ver); > > > > > + if (ret < 0 || soc_ver == 0) { > > > > > + bt_dev_err(hdev, "QCA Failed to get version (%d)", ret); > > > > > + return ret; > > > > > + } > > > > > + bt_dev_info(hdev, "QCA controller version 0x%08x", soc_ver); > > > > > > > > Couldn't we hide some of this in qca_read_soc_version()? > > > > > > > > qca_read_soc_version() could at least do the logging in the error case > > > > (the 'soc_ver == 0' case could be handled there as well), which would > > > > leave us with: > > > > > > > > > > > > ret = qca_read_soc_version(hdev, &soc_ver); > > > > if (ret) > > > > return ret; > > > > > > > > And the same above. > > > > > > > > The controller version can be logged outside of the branch for both > > > > wcn3990 and Rome. > > > > > > > > > } > > > > > - bt_dev_info(hdev, "QCA controller version 0x%08x", soc_ver); > > > > > > > > > > /* Setup patch / NVM configurations */ > > > > > - ret = qca_uart_setup(hdev, qca_baudrate, QCA_ROME, soc_ver); > > > > > + ret = qca_uart_setup(hdev, qca_baudrate, qcadev->btsoc_type, > > > > > soc_ver); > > > > > if (!ret) { > > > > > set_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags); > > > > > qca_debugfs_init(hdev); > > > > > @@ -1061,9 +1209,123 @@ static struct hci_uart_proto qca_proto = { > > > > > .dequeue = qca_dequeue, > > > > > }; > > > > > > > > > > +static const struct qca_vreg_data qca_soc_data = { > > > > > + .soc_type = QCA_WCN3990, > > > > > + .vregs = (struct qca_vreg []) { > > > > > + { "vddio", 1800000, 1800000, 0 }, > > > > > + { "vddxo", 1800000, 1800000, 1 }, > > > > > + { "vddrf", 1304000, 1304000, 1 }, > > > > > + { "vddch0", 3000000, 3312000, 1 }, > > > > > + }, > > > > > + .num_vregs = 4, > > > > > +}; > > > > > > > > I didn't chime in earlier in the discussion with Stephen on the > > > > regulators (https://patchwork.kernel.org/patch/10467911/), however I > > > > agree with him that specifying at load of 1uA doesn't seem to make > > > > much sense. What would happen if the load remained unspecified (or 0)? > > > > > > [Bala]: On RPMh based designs, calling a regulator_set_load with a > > > non-zero > > > value moves the regulator to NPM (high power mode) which is required > > > for BT > > > communication. > > > and call with 0uA moves it to low-power-mode (vote from > > > APPS). > > > Basically whenever BT wants these in NPM it calls set-load with 1. > > > > This assumes that the chip is powered by RPMh regulators, which > > depending on the system may or may not be true. On systems with other > > regulators you are telling the regulator that the max load is 1uA, and > > the regulator might comply, going in a low power mode that does not > > provide enough current for the chip to operate properly. > > > > Doesn't the datasheet of the chip specify actual max currents for > > these consumers that could be used instead of the bogus 1uA? If not > > you could ask the designers of the chip for an approximate number > > (preferably erring on the upper side). > > [Bala]: yes your true, now current values are aligned according to the RPMH > regs packages. > this is not our goal. what ever the package we use wcn3990 should be > platform independent. > I propose an idea that, we will have default current value in driver > i.e current required by regs to turn on wcn3990 and also we will provide > interface in driver > to read current from dts tree. > > i.e. if we have prop for current to the reg in the dts, we will read > the value assigned to prop else we will take default current > > <code snippets> > > qca->vreg_data->vregs[i].name = current; // holds the default current I suppose this should be 'qca->vreg_data->vregs[i].load_uA' > value taken from data provided from deb. this will value remains unchanged. > if (device_property_read_bool(dev, prop_name)) // if we have prop > name enabled then read the value. > device_property_read_u32(dev, prop_name, &vregs->load_uA); It's still not clear why this would be needed. Is 1uA a magic value that is somehow used by RPMh regulators? Earlier you said: > > > [Bala]: On RPMh based designs, calling a regulator_set_load with a > > > non-zero > > > value moves the regulator to NPM (high power mode) which is required > > > for BT > > > communication. > > > and call with 0uA moves it to low-power-mode (vote from > > > APPS). > > > Basically whenever BT wants these in NPM it calls set-load with 1. This is the ->set_load function of the RPMh regulator: static int rpmh_regulator_vrm_set_load(struct regulator_dev *rdev, int load_uA) { struct rpmh_vreg *vreg = rdev_get_drvdata(rdev); unsigned int mode; if (load_uA >= vreg->hw_data->hpm_min_load_uA) mode = REGULATOR_MODE_NORMAL; else mode = REGULATOR_MODE_IDLE; return rpmh_regulator_vrm_set_mode(rdev, mode); } and REGULATOR_MODE_NORMAL translates to HPM for PMIC4 LDOs: static const int pmic_mode_map_pmic4_ldo[REGULATOR_MODE_STANDBY + 1] = { [REGULATOR_MODE_INVALID] = -EINVAL, [REGULATOR_MODE_STANDBY] = PMIC4_LDO_MODE_RETENTION, [REGULATOR_MODE_IDLE] = PMIC4_LDO_MODE_LPM, [REGULATOR_MODE_NORMAL] = PMIC4_LDO_MODE_HPM, [REGULATOR_MODE_FAST] = -EINVAL, }; https://patchwork.kernel.org/patch/10524299/ I don't see how a load value of 1uA would cause the regulator to enter HPM and another higher value wouldn't. HPM is entered as long as 'load_uA >= vreg->hw_data->hpm_min_load_uA', or am I missing something here? -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html