Hi Al,

I love your patch! Perhaps something to improve:

[auto build test WARNING on tty/tty-testing]
[also build test WARNING on linux/master robh/for-next usb/usb-testing linus/master v5.12-rc2 next-20210305]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Al-Cooper/8250-Add-driver-for-Broadcom-UART/20210309-010755
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: nios2-allyesconfig (attached as .config)
compiler: nios2-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/38e38c0d5bd1fd6e256cbb0da5cd0cd1010b9cb6
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Al-Cooper/8250-Add-driver-for-Broadcom-UART/20210309-010755
        git checkout 38e38c0d5bd1fd6e256cbb0da5cd0cd1010b9cb6
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nios2 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   drivers/tty/serial/8250/8250_bcm7271.c: In function 'brcmuart_tx_isr':

quoted

drivers/tty/serial/8250/8250_bcm7271.c:547:6: warning: variable 'length' set but not used [-Wunused-but-set-variable]

     547 |  int length;
         |      ^~~~~~
   drivers/tty/serial/8250/8250_bcm7271.c: At top level:

quoted

drivers/tty/serial/8250/8250_bcm7271.c:1190:12: warning: no previous prototype for 'brcmuart_init' [-Wmissing-prototypes]

    1190 | int __init brcmuart_init(void)
         |            ^~~~~~~~~~~~~

quoted

drivers/tty/serial/8250/8250_bcm7271.c:1198:13: warning: no previous prototype for 'brcmuart_deinit' [-Wmissing-prototypes]

    1198 | void __exit brcmuart_deinit(void)
         |             ^~~~~~~~~~~~~~~


vim +/length +547 drivers/tty/serial/8250/8250_bcm7271.c

   540	
   541	static void brcmuart_tx_isr(struct uart_port *up, u32 isr)
   542	{
   543		struct brcmuart_priv *priv = up->private_data;
   544		struct device *dev = up->dev;
   545		struct uart_8250_port *port_8250 = up_to_u8250p(up);
   546		struct circ_buf	*xmit = &port_8250->port.state->xmit;
 > 547		int length;
   548	
   549		length = udma_readl(priv, REGS_DMA_TX, UDMA_TX_TRANSFER_TOTAL);
   550		if (isr & UDMA_INTR_TX_ABORT) {
   551			if (priv->tx_running)
   552				dev_err(dev, "Unexpected TX_ABORT interrupt\n");
   553			return;
   554		}
   555		priv->tx_running = false;
   556		if (!uart_circ_empty(xmit) && !uart_tx_stopped(up))
   557			brcmuart_tx_dma(port_8250);
   558	}
   559	

---
0-DAY CI Kernel Test Service, Intel Corporation
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